Wikipedia:Vital articles/Level/5/Technology

Vital articles is a list of subjects for which Wikipedia should have corresponding high-quality articles. It serves as a centralized watchlist to track the status of Wikipedia's most essential articles. This is one of the sub-lists of the fifty thousand article Vital articles/Level 5 and is currently under construction.

Quota 3,200 articles.

Total 3,203 articles.

=General =


 * 1)  Technology (Level 1)
 * 2)  Applied science
 * 3)  Appropriate technology
 * 4)  Emerging technologies
 * 5)  Innovation
 * 6)  Invention
 * 7)  Maintenance
 * 8)  Miniaturization
 * 9)  Problem solving
 * 10)  Research and development
 * 11)  Scientific instrument
 * 12)  Simulation
 * 13)  Technological convergence
 * 14)  Technological determinism
 * 15)  Technology adoption life cycle
 * 16)  Technology and society
 * 17)  Technology assessment
 * 18)  Technology life cycle
 * 19)  Technology transfer

Creativity, Vocational education, Intellectual property and Patent are listed in the Society and Social Sciences section; Industrial design in the Arts section. For history of technology, see History#History of science and technology section.

Basics

 * 1)  Engineering (Level 2)
 * 2)  Nanotechnology (Level 4)
 * 3)  Molecular machine
 * 4)  Nuclear technology (Level 4)
 * 5)  Technical drawing (Level 4)
 * 6)  Engineering ethics
 * 7)  Risk management
 * 8)  Engineering management
 * 9)  Engineering design process
 * 10)  Requirements analysis
 * 11)  Problem statement
 * 12)  Feasibility study
 * 13)  Engineering optimization
 * 14)  Computer-aided design
 * 15)  Engineering economics
 * 16)  Engineering statistics
 * 17)  Engineering research
 * 18)  Reverse engineering
 * 19)  Engineering studies

Disciplines

 * 1)  Agricultural engineering
 * 2)  Applied mechanics
 * 3)  Biological engineering
 * 4)  Biochemical engineering
 * 5)  Biomedical engineering (Level 4)
 * 6)  Pharmaceutical engineering
 * 7)  Ceramic engineering
 * 8)  Chemical engineering (Level 4)
 * 9)  Chemical reaction engineering
 * 10)  Nuclear engineering
 * 11)  Molecular engineering
 * 12)  Petroleum engineering
 * 13)  Process engineering
 * 14)  Polymer engineering
 * 15)  Plastics engineering
 * 16)  Civil engineering (Level 3)
 * 17)  Architectural engineering (Level 4)
 * 18)  Construction engineering
 * 19)  Earthquake engineering
 * 20)  Environmental engineering
 * 21)  Geotechnical engineering
 * 22)  Directional drilling
 * 23)  Hydraulic engineering
 * 24)  Mining engineering
 * 25)  Structural engineering
 * 26)  Transportation engineering
 * 27)  Highway engineering
 * 28)   Electrical engineering (Level 4)
 * 29)  Computer engineering
 * 30)  Energy engineering
 * 31)  Power engineering
 * 32)  Telecommunications engineering
 * 33)  Electronic engineering
 * 34)  Control engineering
 * 35)  Microwave engineering
 * 36)  Radio-frequency engineering
 * 37)  Engineering physics
 * 38)  Industrial engineering (Level 4)
 * 39)  Computer-aided engineering
 * 40)  Manufacturing engineering
 * 41)  Mechanical engineering (Level 3)
 * 42)  Aerospace engineering (Level 4)
 * 43)  Mechatronics
 * 44)  Railway engineering
 * 45)  Marine engineering
 * 46)  Automotive engineering (Level 4)
 * 47)  Military engineering (Level 4)
 * 48)  Sanitary engineering
 * 49)  Security engineering
 * 50)  Software engineering (Level 4)
 * 51)  Structural analysis
 * 52)  Systems engineering

=Agriculture =

See Agriculture in the Society category; also see History of Agriculture and related articles under History, or the Everyday life category for basic agricultural products

Basics

 * 1)  Arable land
 * 2)  Crop
 * 3)  Cash crop
 * 4)  Nonfood crop
 * 5)  Fiber crop
 * 6)  Agricultural machinery
 * 7)  Agricultural cycle
 * 8)  Growing season
 * 9)  Season extension
 * 10)  Agricultural land
 * 11)  Pasture

Academic disciplines

 * 1)  Agricultural science (Level 4)
 * 2)  Agricultural chemistry
 * 3)  Agricultural economics
 * 4)  Agricultural philosophy
 * 5)  Agricultural soil science
 * 6)  Agroecology
 * 7)  Agricultural policy
 * 8)  Agricultural geography
 * 9)  Agricultural education
 * 10)   Agricultural extension
 * 11)  Agrometeorology
 * Also see Agricultural engineering in the Engineering section

Agriculture

 * 1)  Beekeeping (Level 4)
 * 2)  Cuniculture
 * 3)  Dairy (Level 4)
 * 4)  Dairy farming
 * 5)  Dryland farming
 * 6)  Desert farming
 * 7)  Heliciculture
 * 8)  Rainfed agriculture
 * 9)  Extensive farming (Level 4)
 * 10)  Gardening (Level 4)
 * 11)  Intensive farming (Level 4)
 * 12)  Mechanised agriculture
 * 13)  Orchard (Level 4)
 * 14)  Organic farming (Level 4)
 * 15)  Genetically modified crops
 * 16)  Sustainable agriculture (Level 4)
 * 17)  Permaculture
 * 18)  Subsistence agriculture (Level 4)
 * 19)  Urban agriculture (Level 4)
 * 20)  Pastoralism
 * 21)  Shifting cultivation
 * 22)  Regenerative agriculture
 * 23)  Animal-free agriculture
 * 24)  Intensive animal farming
 * 25)  Free range
 * 26)  Hydroponics
 * 27)  Sericulture
 * 28)  Viticulture
 * 29)  Fungiculture
 * 30)  Olericulture
 * 31)  Slash-and-burn
 * 32)  Vertical farming
 * 33)  Polyculture
 * 34)  Multiple cropping
 * 35)  Intercropping
 * 36)  Sharecropping
 * 37)  Tenant farmer

Aquaculture

 * 1)  Aquaculture (Level 4)
 * 2)  Mariculture
 * 3)  Algaculture
 * 4)  Aquaculture of giant kelp
 * 5)  Fish farming
 * 6)  Aquaculture of catfish
 * 7)  Aquaculture of salmonids
 * 8)  Aquaculture of tilapia
 * 9)  Freshwater prawn farming
 * 10)  Geoduck aquaculture
 * 11)  Integrated multi-trophic aquaculture
 * 12)   Marine shrimp farming
 * 13)  Offshore aquaculture
 * 14)  Organic aquaculture
 * 15)  Raceway (aquaculture)
 * 16)  Scallop aquaculture
 * 17)  Seaweed farming

Pest and disease control

 * 1)  Aerial application
 * 2)  Acaricide
 * 3)  Agrochemical
 * 4)  Agent Orange
 * 5)  Aldrin
 * 6)  Chemosterilant
 * 7)  DDT
 * 8)  Defoliant
 * 9)  Fumigation
 * 10)  Fungicide
 * 11)  Herbicide
 * 12)  Insecticide
 * 13)  Lindane
 * 14)  Malathion
 * 15)  Methoxychlor
 * 16)  Pest (organism)
 * 17)  Pest control
 * 18)  Biological pest control
 * 19)  Integrated pest management
 * 20)  Pesticide (Level 4)
 * 21)  Rodenticide
 * 22)  Scarecrow
 * 23)  Smother crop
 * 24)  Soil steam sterilization
 * 25)  Tetraethyl pyrophosphate
 * 26)  Toxaphene

Buildings and infrastructure

 * 1)  Apiary
 * 2)  Barn (Level 4)
 * 3)  Farm (Level 4)
 * 4)  Garden (Level 3)
 * 5)  Arboretum
 * 6)  Botanical garden
 * 7)  Chinese garden
 * 8)  English landscape garden
 * 9)  French formal garden
 * 10)  Japanese garden
 * 11)  Persian gardens
 * 12)  Spanish garden
 * 13)  Fishery
 * 14)  Fish hatchery
 * 15)  Granary (Level 4)
 * 16)  Grain elevator
 * 17)  Greenhouse
 * 18)  Orangery
 * 19)  Paddy field
 * 20)  Pavilion
 * 21)  Plant nursery
 * 22)  Raised field
 * 23)  Chinampa
 * 24)  Waru Waru
 * 25)  Seedbed
 * 26)  Silo (Level 4)
 * 27)  Stable (Level 4)
 * 28)  Terrace (earthworks)
 * 29)  Ranch

Animal husbandry

 * 1)  Animal husbandry (Level 3)
 * 2)  Animal slaughter
 * 3)  Breed (Level 4)
 * 4)  Culling
 * 5)  Domestication (Level 3)
 * 6)  Goat farming
 * 7)  Animal feed
 * 8)  Fodder
 * 9)  Hay (Level 4)
 * 10)  Straw
 * 11)  Forage
 * 12)  Fish meal
 * 13)  Livestock (Level 4)
 * 14)  Pig farming
 * 15)  Poultry farming
 * 16)  Selective breeding (Level 4)
 * 17)  Animal breeding
 * 18)  Purebred
 * 19)  Sheep farming
 * 20)  Slaughterhouse
 * 21)  Antibiotic use in livestock

Basics

 * 1)  Agronomy (Level 4)
 * 2)  Plant breeding (Level 4)
 * 3)  Cultivar (Level 4)
 * 4)  Crop yield

Agronomical techniques

 * 1)  Nutrient management
 * 2)  Fertilizer (Level 3)
 * 3)  Compost
 * 4)  Vermicompost
 * 5)  Green manure
 * 6)  Guano
 * 7)  Manure
 * 8)  Harvest (Level 4)
 * 9)  Threshing
 * 10)  Winnowing
 * 11)  Irrigation (Level 4)
 * 12)  Tillage (Level 4)
 * 13)  Silage
 * 14)  Sowing
 * 15)  Postharvest

Soil and soil management
See "Pedology" in Earth Science
 * 1)  Beneficial organism
 * 2)  Cover crop
 * 3)  Crop rotation
 * 4)  Mulch
 * 5)  Plastic mulch
 * 6)  Nitrogen fixation
 * 7)  Norfolk four-course system
 * 8)  No-till farming
 * 9)  Three-field system
 * 10)  Soil salinity control

Horticulture

 * 1)  Horticulture (Level 4)
 * 2)  Espalier
 * 3)  Floriculture
 * 4)  Grafting
 * 5)  Layering
 * 6)  Plant propagation
 * 7)  Pollarding
 * 8)  Pollination management
 * 9)  Pruning
 * 10)  Smudge pot
 * 11)  Topiary
 * 12)  Transplanting
 * 13)  Basal shoot
 * 14)  Pomology
 * 15)  Companion planting
 * 16)  Genetically modified tree
 * 17)  Indigenous horticulture
 * 18)  Urban horticulture
 * 19)  Hardiness (plants)
 * 20)  Hardiness zone
 * 21)  Drought tolerance
 * 22)  Tropical horticulture

Hunting and fishing

 * 1)  Fishing line
 * 2)  Dropline
 * 3)  Longline fishing
 * 4)  Trotline
 * 5)  Fishing net
 * 6)  Gillnetting
 * 7)  Seine fishing
 * 8)  Fishing rod
 * 9)  Fish hook
 * 10)  Fishing lure
 * 11)  Fishing reel
 * 12)  Fishing float
 * 13)  Fish trap
 * 14)  Crab trap
 * 15)  Fishing weir
 * 16)  Lobster trap
 * 17)  Trapping
 * 18)  Bait (luring substance)

Trees and forestry

 * 1)  Agroforestry
 * 2)  Arboriculture
 * 3)  Silviculture
 * 4)  Coppicing
 * 5)  Controlled burn

Agriculture, labor and economy

 * 1)  Community-supported agriculture
 * 2)  Teikei
 * 3)  Corporate farming
 * 4)  Family farm
 * 5)  Agricultural cooperative
 * 6)  Working animal
 * 7)  Agribusiness
 * 8)  Agricultural marketing

Agriculture and ecology

 * 1)  Environmental impact of agriculture
 * 2)  Agricultural expansion
 * 3)  Agricultural pollution

Agricultural machinery and tools
See "Agricultural tools" and "Farm and Garden Machinery" in Technology : Machinery and tools

=Biotechnology =

See also : Selective Breeding in Agriculture; Fermentation in Biology


 * 1)  Biotechnology (Level 3)
 * 2)  Cell culture
 * 3)  Plant tissue culture
 * 4)  Genetic engineering (Level 3)
 * 5)  Recombinant DNA
 * 6)  Genetically modified organism (Level 4)
 * 7)  CRISPR
 * 8)  Molecular cloning
 * 9)  Cloning (Level 4)
 * 10)  Somatic cell nuclear transfer
 * 11)  Gel electrophoresis (Level 4)
 * 12)  Polymerase chain reaction (Level 4)
 * 13)  Western blot
 * 14)  Cyborg
 * 15)  Whole genome sequencing
 * 16)  Tissue engineering
 * 17)  Biochip
 * 18)  De-extinction
 * 19)  Genome editing
 * 20)  Nuclear transfer
 * 21)  Pharming (genetics)
 * 22)  Biomimetics
 * 23)  DNA microarray
 * 24)  Micropropagation
 * 25)  Biological hazard
 * 26)  Bioterrorism
 * 27)  Agro-terrorism
 * 28)  Pharmacogenomics
 * 29)  Biopharmaceutical
 * 30)  Genetic testing
 * 31)  Synthetic biopolymer
 * 32)  Biomaterial
 * 33)  Agricultural biotechnology
 * 34)  Environmental biotechnology
 * 35)  Bioreactor
 * 36)  Gene therapy
 * 37)  Stem-cell therapy
 * 38)  Antisense therapy
 * 39)  Organ printing
 * 40)  Protein engineering
 * 41)  Activated sludge
 * 42)   Anaerobic digestion
 * 43)  Bioleaching
 * 44)  Biomining
 * 45)  Somatic fusion

=Communication, media, and computing technology =

For abstract topics in computer science, see Mathematics: Theoretical computer science (Level 5)

Computing and information technology basics

 * 1)  Computing (Level 4)
 * 2)  Information technology (Level 4)
 * 3)  Abacus (Level 4)
 * 4)  Calculator (Level 4)
 * 5)  Counting board
 * 6)  Data (computer science) (Level 4)
 * 7)  Data communication (Level 4)
 * 8)  Metadata
 * 9)  File sharing
 * 10)  Human–computer interaction
 * 11)  Open source

Computer science

 * 1)  Computer science (Level 3)
 * 2)  Artificial intelligence (Level 3)
 * 3)  Computer architecture (Level 4)
 * 4)  Computer simulation (Level 4)
 * 5)  Parallel computing (Level 4)
 * 6)  General-purpose computing on graphics processing units
 * 7)  Augmented reality
 * 8)  Mixed reality
 * 9)  Virtual reality
 * 10)  Concurrent computing
 * 11)  Monitor (synchronization)
 * 12)  Floating-point arithmetic
 * 13)  Real-time computing
 * 14)  Computer graphics (computer science)
 * 15)  Color management
 * 16)  Transform, clipping, and lighting

Computer architecture concepts

 * 1)  Cache (computing)
 * 2)  Cache coherence
 * 3)  Distributed computing
 * 4)  Computer cluster
 * 5)   Grid computing
 * 6)  Cloud computing
 * 7)  Optical computing
 * 8)  DNA computing
 * 9)   Quantum computing
 * 10)  Von Neumann architecture
 * 11)  8-bit computing
 * 12)  16-bit computing
 * 13)  32-bit computing
 * 14)  64-bit computing
 * 15)  Endianness
 * 16)  Multithreading (computer architecture)
 * 17)  Multiprocessing
 * 18)  Instruction set architecture
 * 19)  x86
 * 20)  x86-64
 * 21)  ARM architecture family
 * 22)  IBM POWER architecture
 * 23)  MIPS architecture
 * 24)  Very long instruction word
 * 25)  System time
 * 26)  Epoch (computing)
 * 27)  Unix time

Computer security

 * 1)   Computer security (Level 4)
 * 2)  Firewall (computing)
 * 3)  Transport Layer Security
 * 4)  Security bug
 * 5)  Zero-day vulnerability
 * 6)  Denial-of-service attack
 * 7)  Botnet
 * 8)  Copy protection
 * 9)  Digital rights management
 * 10)  Malware (Level 4)
 * 11)  Computer virus
 * 12)  Computer worm
 * 13)  Trojan horse (computing)
 * 14)  Ransomware
 * 15)   Spyware
 * 16)  Keystroke logging
 * 17)   Cryptography (Level 3)
 * 18)  Blockchain
 * 19)  Block cipher
 * 20)   Brute-force attack
 * 21)  Caesar cipher
 * 22)  Cipher
 * 23)  Cryptanalysis
 * 24)  Digital signature
 * 25)  Encryption (Level 4)
 * 26)   Enigma machine
 * 27)  Key (cryptography)
 * 28)  One-time pad
 * 29)  Public-key cryptography
 * 30)  Diffie–Hellman key exchange
 * 31)  RSA (cryptosystem)
 * 32)  Symmetric-key algorithm
 * 33)  Authentication (Level 4)
 * 34)  Password
 * 35)  Security token
 * 36)  Multi-factor authentication
 * 37)  Security through obscurity
 * 38)  Obfuscation (software)
 * 39)  Steganography
 * 40)  Zombie (computing)

Computer hardware

 * 1)  Computer hardware (Level 4)
 * 2)  Computer (Level 2)
 * 3)  Desktop computer
 * 4)  Gaming computer
 * 5)  Home computer
 * 6)  IBM PC–compatible
 * 7)  Laptop
 * 8)  Mainframe computer
 * 9)  Mobile device (Level 4)
 * 10)  Personal computer (Level 4)
 * 11)  Supercomputer (Level 4)
 * 12)  Tablet computer
 * 13)  Wearable computer
 * 14)  Workstation
 * 15)  Booting (Level 4)
 * 16)  BIOS
 * 17)  UEFI
 * 18)  Multi-booting
 * 19)  Reboot
 * 20)  Processor (computing)
 * 21)   Central processing unit (Level 4)
 * 22)  Microprocessor
 * 23)  Multi-core processor
 * 24)  Coprocessor
 * 25)  Motherboard
 * 26)  Processor register
 * 27)  Floating-point unit
 * 28)  Graphics processing unit
 * 29)  Arithmetic logic unit
 * 30)  Digital signal processor
 * 31)  Bus (computing)
 * 32)  SATA
 * 33)  Parallel ATA
 * 34)  Industry Standard Architecture
 * 35)  Peripheral Component Interconnect
 * 36)  PCI Express
 * 37)  Front-side bus
 * 38)  Expansion card
 * 39)  Sound card
 * 40)  Graphics card
 * 41)  PC Card
 * 42)  ExpressCard
 * 43)  Modem
 * 44)  Device driver
 * 45)  Intel High Definition Audio
 * 46)  Moore's law
 * 47)  Clock rate
 * 48)  Embedded system
 * 49)  Real-time clock
 * 50)  Computer case
 * 51)  Computer cooling
 * 52)  Analog computer
 * 53)  Stored-program computer
 * 54)  Hardware acceleration
 * 55)  Plug and play

User interface

 * 1)  User interface (Level 4)
 * 2)  Graphical user interface
 * 3)  Window (computing)
 * 4)   X Window System
 * 5)  Command-line interface
 * 6)  Cut, copy, and paste
 * 7)  Peripheral
 * 8)  Computer keyboard
 * 9)  Computer monitor (Level 4)
 * 10)  Pointing device
 * 11)  Computer mouse (Level 4)
 * 12)  Touchpad
 * 13)  Touchscreen (Level 4)
 * 14)  Virtual reality headset
 * 15)  Computer port (hardware)
 * 16)  IEEE 1394
 * 17)  USB
 * 18)  USB-C
 * 19)  D-subminiature
 * 20)  Digital Visual Interface
 * 21)  DisplayPort
 * 22)   HDMI
 * 23)  VGA connector
 * 24)  Thunderbolt (interface)
 * 25)  Webcam

Computer software

 * 1)  Software (Level 4)
 * 2)  Application software
 * 3)  Chatbot
 * 4)  Database (Level 4)
 * 5)  Data mining
 * 6)  Big data
 * 7)  Emulator
 * 8)  Media player software
 * 9)  Mobile app
 * 10)  Open-source software (Level 4)
 * 11)  Spreadsheet (Level 4)
 * 12)  System software
 * 13)  Web application
 * 14)  Webmail
 * 15)  Web content management system
 * 16)  Web browser (Level 4)
 * 17)  Word processor (Level 4)
 * 18)  Desktop publishing
 * 19)  Plug-in (computing)
 * 20)  POSIX
 * 21)  GNU Project
 * 22)  Input method

Operating systems

 * 1)  Firmware
 * 2)  Operating system (Level 4)
 * 3)  Real-time operating system
 * 4)  Virtual machine
 * 5)   Kernel (operating system)
 * 6)  Job (computing)
 * 7)  Task (computing)
 * 8)  Thrashing (computer science)
 * 9)  Thread (computing)
 * 10)  Preemption (computing)
 * 11)  Process (computing)
 * 12)  Computer multitasking
 * 13)  Scheduling (computing)
 * 14)  System call
 * 15)  Time-sharing
 * 16)  Working set

Data storage and memory
For units of information (bit, byte, megabyte, etc.), see Physical sciences/Basics and measurement
 * 1)  Computer file (Level 4)
 * 2)  Backup
 * 3)  Barcode (Level 4)
 * 4)  QR code
 * 5)  File system (Level 4)
 * 6)  HFS Plus
 * 7)  File Allocation Table
 * 8)  NTFS
 * 9)  ext4
 * 10)  ISO 9660
 * 11)  Universal Disk Format
 * 12)  Directory (computing)
 * 13)  Filename extension
 * 14)  Data storage (Level 4)
 * 15)  Computer data storage
 * 16)  Cloud storage
 * 17)  RAID
 * 18)  Disk partitioning
 * 19)  Computer memory
 * 20)  Binary file
 * 21)  Text file
 * 22)  Formatted text
 * 23)  Plain text

File format

 * 1)  File format
 * 2)  Archive file
 * 3)  ZIP (file format)
 * 4)  RAR (file format)
 * 5)  7z
 * 6)  Document file format
 * 7)  Office Open XML
 * 8)  OpenDocument
 * 9)  PDF
 * 10)  Image file format
 * 11)  GIF
 * 12)  JPEG
 * 13)  TIFF
 * 14)  PNG
 * 15)  SVG
 * 16)  Audio coding format
 * 17)  WAV
 * 18)  MP3
 * 19)  Advanced Audio Coding
 * 20)  Video coding format
 * 21)  Advanced Video Coding
 * 22)  DivX
 * 23)  Container format
 * 24)  MPEG-4
 * 25)  WebM
 * 26)  Ogg

Volatile memory

 * 1)  Volatile memory
 * 2)  Random-access memory (Level 4)
 * 3)  Dynamic random-access memory
 * 4)  Static random-access memory
 * 5)  Virtual memory

Non-volatile memory

 * 1)  Non-volatile memory
 * 2)  Read-only memory (Level 4)
 * 3)  Magnetic storage
 * 4)   Floppy disk
 * 5)  Hard disk drive (Level 4)
 * 6)  Magnetic tape (Level 4)
 * 7)  Magnetic-tape data storage
 * 8)  VHS
 * 9)  Videotape
 * 10)  Betamax
 * 11)  Flash memory
 * 12)  USB flash drive
 * 13)  Solid-state drive
 * 14)  Memory card (Level 4)
 * 15)  CompactFlash
 * 16)  SD card
 * 17)  MultiMediaCard
 * 18)  Universal Flash Storage
 * 19)  Optical disc (Level 4)
 * 20)  Compact disc
 * 21)  DVD
 * 22)  LaserDisc
 * 23)  HD DVD
 * 24)  Blu-ray

Networks

 * 1)  Computer network (Level 4)
 * 2)  Intranet
 * 3)  Email (Level 4)
 * 4)   Spamming
 * 5)  Simple Mail Transfer Protocol
 * 6)  Internet Message Access Protocol
 * 7)  Ethernet (Level 4)
 * 8)  Router (computing) (Level 4)
 * 9)  Routing
 * 10)  Wi-Fi (Level 4)
 * 11)  Bluetooth
 * 12)  Cellular network
 * 13)  GSM
 * 14)  Server (computing)
 * 15)  Client–server model
 * 16)  Network topology
 * 17)  Network switch
 * 18)  Network packet
 * 19)  Network interface controller
 * 20)  Node (networking)
 * 21)  Internet of things
 * 22)  Wireless mesh network
 * 23)  Content delivery network
 * 24)  Private network
 * 25)  Subnet
 * 26)  Tunneling protocol
 * 27)  Proxy server
 * 28)  Reverse proxy

Internet
For Internet culture, see Society and social sciences/Culture#Internet medium
 * 1)  Internet (Level 3)
 * 2)  ARPANET
 * 3)  CSS
 * 4)  Communication protocol
 * 5)  Common Gateway Interface
 * 6)  File Transfer Protocol
 * 7)  Hashtag
 * 8)  HTML (Level 4)
 * 9)  HTML5
 * 10)  HTTP (Level 4)
 * 11)  HTTPS
 * 12)  Instant messaging
 * 13)  Online chat
 * 14)  IRC
 * 15)  Internet protocol suite (Level 4)
 * 16)  Internet Protocol
 * 17)  IP address
 * 18)  IPv4
 * 19)  IPv6
 * 20)  Transmission Control Protocol
 * 21)  Internet service provider
 * 22)  Peer-to-peer file sharing
 * 23)  BitTorrent
 * 24)  EDonkey network
 * 25)   Napster
 * 26)  Social media (Level 4)
 * 27)  Blog
 * 28)  Bulletin board system
 * 29)  Chat room
 * 30)  Internet forum
 * 31)  Online dating
 * 32)  Social networking service
 * 33)  Usenet
 * 34)  Web 2.0
 * 35)  Search engine (Level 4)
 * 36)  Tor (network)
 * 37)  Website (Level 4)
 * 38)  Home page
 * 39)   Wiki
 * 40)   World Wide Web (Level 4)
 * 41)  Dark web
 * 42)  Deep web

Cloud server

 * 1)  Amazon Web Services
 * 2)  Google Cloud Platform

Multimedia

 * 1)  Flickr
 * 2)   Netflix
 * 3)  Pornhub
 * 4)  Steam (service)
 * 5)   YouTube (Level 4)

E-commerce

 * 1)  Alipay
 * 2)  Craigslist
 * 3)  Taobao

Portals/Platform sites

 * 1)  MSN
 * 2)  Naver
 * 3)  Yahoo!

Utility

 * 1)  GitHub
 * 2)  Google Maps
 * 3)  Internet Archive
 * 4)  IMDb
 * 5)  Rotten Tomatoes
 * 6)  Urban Dictionary
 * 7)   Wikipedia (Level 4)

Science

 * 1)  Berkeley Open Infrastructure for Network Computing

Search engines

 * 1)  Google Search
 * 2)  Microsoft Bing

Social network and blogging

 * 1)  2channel
 * 2)   4chan
 * 3)  Blogger (service)
 * 4)   DeviantArt
 * 5)  Discord
 * 6)   Facebook (Level 4)
 * 7)  ICQ
 * 8)  Instagram
 * 9)  Line (software)
 * 10)  LinkedIn
 * 11)  Myspace
 * 12)  Pinterest
 * 13)  Reddit
 * 14)  Slack (software)
 * 15)  Skype
 * 16)  Snapchat
 * 17)  Telegram (software)
 * 18)  Tencent QQ
 * 19)  TikTok
 * 20)  Tinder (app)
 * 21)  Tumblr
 * 22)  Twitch (service)
 * 23)   Twitter
 * 24)  Weibo
 * 25)  Vine (service)
 * 26)  VK (service)
 * 27)  WeChat
 * 28)  WhatsApp

Software development: General

 * 1)  Software development
 * 2)  Software prototyping
 * 3)  Reusability
 * 4)  Software portability
 * 5)  Transparency (human–computer interaction)
 * 6)  Library (computing)
 * 7)  Formal specification
 * 8)  Formal verification
 * 9)  Software design
 * 10)  Abstraction (computer science)
 * 11)  Variable (computer science)
 * 12)  Function (computer programming)
 * 13)  Pointer (computer programming)
 * 14)  Recursion (computer science)
 * 15)  Iteration
 * 16)  Computer programming (Level 4)
 * 17)  Flowchart
 * 18)  Source code
 * 19)  Bytecode
 * 20)  Object code
 * 21)  Executable
 * 22)  .exe
 * 23)  Parameter (computer programming)
 * 24)  Collation
 * 25)  Universal Product Code
 * 26)  Character encoding (Level 4)
 * 27)   ASCII
 * 28)  Mojibake
 * 29)  Unicode
 * 30)  UTF-8
 * 31)  Error correction code
 * 32)  Compiler (Level 4)
 * 33)  Interpreter (computing)
 * 34)  Control flow
 * 35)  Macro (computer science)
 * 36)  Regular expression
 * 37)  Calling convention
 * 38)   Programming language (Level 4)
 * 39)  Programming paradigm (Level 4)
 * 40)   Functional programming (Level 4)
 * 41)  Structured programming (Level 4)
 * 42)  Modular programming
 * 43)  Object-oriented programming (Level 4)
 * 44)  Declarative programming
 * 45)   Imperative programming
 * 46)  Logic programming
 * 47)   API
 * 48)  Carbon (API)
 * 49)  Cocoa (API)
 * 50)  Open Database Connectivity
 * 51)  Windows API
 * 52)  DirectX
 * 53)  Direct3D
 * 54)  OpenGL
 * 55)  Vulkan
 * 56)  Glide (API)
 * 57)  Software testing
 * 58)  Software bug
 * 59)  Debugging
 * 60)  Application checkpointing
 * 61)  Exception handling
 * 62)  Version control
 * 63)  Software maintenance
 * 64)  Software documentation

Programming languages

 * 1)  Syntax (programming languages)
 * 2)  Metasyntax
 * 3)  Backus–Naur form
 * 4)  Type conversion
 * 5)  Data type
 * 6)   Delimiter
 * 7)  Operator overloading
 * 8)  Language binding
 * 9)  Low-level programming language
 * 10)  Machine code
 * 11)  Assembly language (Level 4)
 * 12)  High-level programming language
 * 13)   C (programming language) (Level 4)
 * 14)   C++
 * 15)  C Sharp (programming language)
 * 16)  Objective-C
 * 17)  Delphi (software)
 * 18)  Haskell
 * 19)   Java (programming language) (Level 4)
 * 20)  Kotlin (programming language)
 * 21)  Lisp (programming language)
 * 22)  Lua (programming language)
 * 23)  Scala (programming language)
 * 24)  Swift (programming language)
 * 25)  Visual Basic (.NET)
 * 26)  Shading language
 * 27)  R (programming language)

Data modeling languages

 * 1)  SQL

Markup languages

 * 1)  XML

Scripting languages

 * 1)   Python (programming language)
 * 2)  Ruby (programming language)
 * 3)   PHP
 * 4)   Perl
 * 5)  JavaScript (Level 4)
 * 6)  Shell script

"Historical" languages

 * 1)  ALGOL
 * 2)   BASIC
 * 3)  Pascal (programming language)
 * 4)  Fortran
 * 5)  Ada (programming language)
 * 6)   COBOL

Artificial intelligence concepts

 * 1)  AI alignment
 * 2)  Artificial general intelligence
 * 3)  Neural network (machine learning)
 * 4)  Computer chess
 * 5)  Computer Go
 * 6)  Existential risk from artificial general intelligence
 * 7)  Generative artificial intelligence
 * 8)  Large language model
 * 9)  Machine learning
 * 10)  Deep learning
 * 11)  Natural language processing
 * 12)  Speech recognition
 * 13)  Machine translation
 * 14)  Philosophy of artificial intelligence
 * 15)   Technological singularity
 * 16)  Turing test
 * 17)  Weak artificial intelligence

Other media and communication technology
See also Arts: Literature; Society: Mass media Physical and analog media are also included here


 * 1)  Broadcasting (Level 3)
 * 2)  Audiobook
 * 3)  Communications satellite (Level 4)
 * 4)  Display device
 * 5)  Cathode-ray tube (Level 4)
 * 6)  Flat-panel display (Level 4)
 * 7)  Liquid-crystal display (Level 4)
 * 8)  microLED
 * 9)  OLED
 * 10)  Plasma display
 * 11)  Projection screen
 * 12)  Ebook
 * 13)  E-reader
 * 14)  Image (Level 4)
 * 15)  Image scanner (Level 4)
 * 16)   Mail (Level 3)
 * 17)  Courier (Level 4)
 * 18)  Postage stamp (Level 4)
 * 19)  Pigeon post
 * 20)  Autopen
 * 21)  Manuscript
 * 22)  Scroll
 * 23)  Portable media player
 * 24)  Printing (Level 3)
 * 25)  Book (Level 2)
 * 26)  ISBN
 * 27)  Photocopier (Level 4)
 * 28)  Printer (computing) (Level 4)
 * 29)  Printing press (Level 4)
 * 30)  Font
 * 31)  Movable type
 * 32)  Print on demand
 * 33)  Radio (Level 3)
 * 34)  Amateur radio (Level 4)
 * 35)  Antenna tuner
 * 36)  Radio broadcasting (Level 4)
 * 37)  FM broadcasting
 * 38)  AM broadcasting
 * 39)  Shortwave radio
 * 40)  Radio receiver
 * 41)  Crystal radio
 * 42)  Superheterodyne receiver
 * 43)  Transistor radio
 * 44)  Software-defined radio
 * 45)  Transmitter
 * 46)  Walkie-talkie
 * 47)  Smartwatch
 * 48)  Sound recording and reproduction (Level 4)
 * 49)   Cassette tape
 * 50)  Loudspeaker (Level 4)
 * 51)  Phonograph
 * 52)   Phonograph record
 * 53)  Headphones
 * 54)  Microphone (Level 4)
 * 55)   Speech synthesis (Level 4)
 * 56)   Telecommunications (Level 3)
 * 57)  Demodulation
 * 58)  Fax
 * 59)  Modulation (Level 4)
 * 60)  Amplitude modulation
 * 61)  Frequency-hopping spread spectrum
 * 62)  Frequency modulation
 * 63)  Frequency-shift keying
 * 64)  Phase modulation
 * 65)  Submarine communications cable
 * 66)  Telegraphy (Level 4)
 * 67)  Electrical telegraph
 * 68)  Flag semaphore
 * 69)  Telephony
 * 70)  Code-division multiple access
 * 71)  Telephone (Level 3)
 * 72)  Landline
 * 73)  Mobile phone (Level 3)
 * 74)  Satellite phone
 * 75)  Smartphone (Level 4)
 * 76)  Text messaging (Level 4)
 * 77)  Videotelephony
 * 78)   Television (Level 3)
 * 79)  Analog television
 * 80)  NTSC
 * 81)  PAL
 * 82)  SECAM
 * 83)  Color television
 * 84)  Digital television
 * 85)  ATSC standards
 * 86)  Digital multimedia broadcasting
 * 87)  Digital Terrestrial Multimedia Broadcast
 * 88)  DVB
 * 89)  ISDB
 * 90)  High-definition television
 * 91)  Ultra-high-definition television
 * 92)  Mechanical television
 * 93)  Cable television (Level 4)
 * 94)  Satellite television (Level 4)
 * 95)  Streaming media
 * 96)  Streaming television
 * 97)  Terrestrial television
 * 98)   Typewriter (Level 4)
 * 99)  QWERTY
 * 100)  Video (Level 4)
 * 101)  Digital video
 * 102)  Digital video recorder
 * 103)  Video camera (Level 4)
 * 104)  Videocassette recorder

Specific hardware
See also video game hardware section under games for early Home Computers
 * 1)  Amazon Kindle
 * 2)  Amiga
 * 3)  Arduino
 * 4)  Chromebook
 * 5)   Commodore 64
 * 6)  Deep Blue (chess computer)
 * 7)   iPad
 * 8)  iPhone (Level 4)
 * 9)   iPod
 * 10)   Mac (computer) (Level 4)
 * 11)  iMac
 * 12)  PC-98
 * 13)  Raspberry Pi
 * 14)  Samsung Galaxy
 * 15)  Walkman
 * 16)  ZX Spectrum

Early computers

 * 1)  Analytical engine
 * 2)  Antikythera mechanism
 * 3)  Atanasoff–Berry computer
 * 4)  Atlas (computer)
 * 5)  Colossus computer
 * 6)  Difference engine
 * 7)  EDSAC
 * 8)  EDVAC
 * 9)  ENIAC (Level 4)
 * 10)  IBM Personal Computer
 * 11)  IBM 7030 Stretch
 * 12)  Manchester computers
 * 13)  Harvard Mark I
 * 14)  TRS-80
 * 15)  UNIVAC I
 * 16)  Whirlwind I
 * 17)  Z3 (computer)
 * 18)  Apple II

Artificial Intelligence

 * 1)  AlphaGo
 * 2)  ChatGPT

Browsers

 * 1)   Firefox
 * 2)  Google Chrome
 * 3)   Internet Explorer
 * 4)  Microsoft Edge
 * 5)   Safari (web browser)

Communication

 * 1)   Gmail
 * 2)  Microsoft Outlook

Development

 * 1)  "Hello, World!" program
 * 2)  Visual Studio

Multimedia

 * 1)  Adobe Creative Suite
 * 2)  Adobe Flash
 * 3)  Adobe Photoshop
 * 4)  GarageBand
 * 5)  GIMP
 * 6)  Inkscape
 * 7)   iTunes
 * 8)  Microsoft Paint
 * 9)  VLC media player

Office and data management

 * 1)  Adobe Acrobat
 * 2)   Emacs
 * 3)  LibreOffice
 * 4)  Microsoft Office
 * 5)  Microsoft Excel
 * 6)  Microsoft PowerPoint
 * 7)  Microsoft Word
 * 8)  MySQL
 * 9)   TeX
 * 10)  WinRAR
 * 11)  Vim (text editor)

Operating Systems

 * 1)  Android (operating system) (Level 4)
 * 2)  iOS
 * 3)  DOS
 * 4)  MS-DOS (Level 4)
 * 5)  Mac operating systems
 * 6)  Classic Mac OS
 * 7)   macOS
 * 8)   Microsoft Windows (Level 4)
 * 9)  Windows 3.1
 * 10)  Windows 9x
 * 11)  Windows NT
 * 12)   Windows XP
 * 13)  Windows 7
 * 14)  Windows 10
 * 15)  Symbian
 * 16)  Unix (Level 4)
 * 17)  Unix-like
 * 18)   Linux (Level 4)
 * 19)  Debian

Science and Engineering

 * 1)  AutoCAD
 * 2)  MATLAB

System

 * 1)  GDK
 * 2)   KDE
 * 3)  Wine (software)

Virtualization

 * 1)  Java virtual machine
 * 2)  VirtualBox
 * 3)  VMware

=Electronics =

For topics in electromagnetism, see Physics:Electromagnetism

Electronics: General

 * 1)  Electronics (Level 3)
 * 2)  Analogue electronics
 * 3)  Digital electronics
 * 4)  Circuit design (Level 4)
 * 5)  Electronic design automation
 * 6)  Printed circuit board (Level 4)
 * 7)  SPICE
 * 8)  Electronic circuit
 * 9)  Multimeter

Components

 * 1)  Electronic component
 * 2)   Amplifier (Level 4)
 * 3)  Operational amplifier
 * 4)  Vacuum tube (Level 4)
 * 5)  Capacitor (Level 4)
 * 6)  Ceramic capacitor
 * 7)  Electrolytic capacitor
 * 8)  Film capacitor
 * 9)  Leyden jar
 * 10)  Supercapacitor
 * 11)  Variable capacitor
 * 12)  Diode (Level 4)
 * 13)  Light-emitting diode (Level 4)
 * 14)  Electrical connector (Level 4)
 * 15)  Inductor (Level 4)
 * 16)  Power supply (Level 4)
 * 17)  Current source
 * 18)  Voltage source
 * 19)  Resistor (Level 4)
 * 20)  Potentiometer
 * 21)  Switch (Level 4)
 * 22)  Knife switch
 * 23)  Relay (Level 4)
 * 24)  Rotary switch
 * 25)  Transducer
 * 26)  Actuator
 * 27)  Solenoid
 * 28)  Sensor (Level 4)
 * 29)  Avalanche photodiode
 * 30)  Photodiode
 * 31)  Photomultiplier tube
 * 32)  Phototube
 * 33)  Stretch sensor
 * 34)  Thermistor
 * 35)  Thermocouple
 * 36)   Transformer (Level 4)

Consumer electronics

 * 1)  Consumer electronics (Level 4)
 * 2)  AC adapter
 * 3)  Remote control (Level 4)

Digital logic

 * 1)  Asynchronous circuit
 * 2)  Logic gate
 * 3)  AND gate
 * 4)  Digital buffer
 * 5)  Inverter (logic gate)
 * 6)  NAND gate
 * 7)  NOR gate
 * 8)  OR gate
 * 9)  XOR gate
 * 10)  XNOR gate
 * 11)  Adder (electronics)
 * 12)  Binary multiplier
 * 13)  Subtractor
 * 14)  Flip-flop (electronics)
 * 15)  Synchronous circuit
 * 16)  Clock domain crossing

Functional circuits

 * 1)  Bridge circuit
 * 2)  Wheatstone bridge
 * 3)  Electronic oscillator
 * 4)  Clock generator
 * 5)  Clock signal
 * 6)  Crystal oscillator
 * 7)  Variable-frequency oscillator
 * 8)  Frequency mixer
 * 9)  Gyrator
 * 10)  Negative impedance converter
 * 11)  Power inverter
 * 12)  Rectifier
 * 13)  Diode bridge
 * 14)  Voltage regulator

Semiconductors

 * 1)  Semiconductor device (Level 3)
 * 2)  Integrated circuit (Level 3)
 * 3)  Application-specific integrated circuit
 * 4)  Charge-coupled device (Level 4)
 * 5)  Field-programmable gate array
 * 6)  System on a chip
 * 7)  Network on a chip
 * 8)  Very-large-scale integration
 * 9)  Transistor (Level 4)
 * 10)  Bipolar junction transistor
 * 11)  Field-effect transistor
 * 12)  MOSFET
 * 13)  Transistor–transistor logic
 * 14)  CMOS

Signal processing

 * 1)  Signal processing (Level 4)
 * 2)  Digital signal
 * 3)  Analog-to-digital converter
 * 4)  Digital-to-analog converter
 * 5)  Filter (signal processing) (Level 4)
 * 6)  All-pass filter
 * 7)  Lattice phase equaliser
 * 8)  Band-pass filter
 * 9)  Mechanical filter
 * 10)  High-pass filter
 * 11)  Low-pass filter
 * 12)  Multiplexing
 * 13)  Noise (electronics)
 * 14)  Signal-to-noise ratio (Level 4)
 * 15)  Oscilloscope (Level 4)
 * 16)  Sampling (signal processing)
 * 17)  Nyquist–Shannon sampling theorem

Signal transmission

 * 1)  Antenna (radio) (Level 4)
 * 2)  Antenna array
 * 3)  Electromagnetic shielding
 * 4)  Faraday cage
 * 5)  Transmission line
 * 6)  Coaxial cable
 * 7)  Waveguide (Level 4)

=Energy =

Energy: General

 * 1)  Energy development
 * 2)  Fire (Level 2)
 * 3)  Propellant
 * 4)  Renewable energy (Level 3)
 * 5)  Sustainable energy

Fuel

 * 1)  Fuel (Level 4)
 * 2)  Biofuel (Level 4)
 * 3)  Biomass (energy)
 * 4)  Charcoal (Level 4)
 * 5)  Fossil fuel (Level 3)
 * 6)  Coal (Level 3)
 * 7)  Coke (fuel)
 * 8)  Fracking
 * 9)  Natural gas (Level 3)
 * 10)  Liquefied natural gas
 * 11)  Liquefied petroleum gas
 * 12)  Oil well (Level 4)
 * 13)  Petroleum reservoir
 * 14)  Oil platform
 * 15)  Hydrogen economy
 * 16)  Oil refinery (Level 4)
 * 17)  Aviation fuel
 * 18)  Jet fuel
 * 19)  Diesel fuel
 * 20)  Fuel oil
 * 21)  Gasoline (Level 4)
 * 22)  Kerosene (Level 4)
 * 23)  Liquid fuel
 * 24)  Nuclear fuel
 * 25)  Nuclear fuel cycle

Heating and cooling

 * 1)  Heating, ventilation, and air conditioning (Level 4)
 * 2)  Heat pump
 * 3)  Air conditioning (Level 4)
 * 4)  Evaporative cooler
 * 5)  Passive cooling
 * 6)  Windcatcher
 * 7)  Boiler
 * 8)  Fan (machine)
 * 9)  Ceiling fan
 * 10)  Heat exchanger
 * 11)  Refrigeration (Level 3)
 * 12)  Yakhchāl

Lighting

 * 1)  Candle (Level 4)
 * 2)  Electric light (Level 3)
 * 3)  Flashlight
 * 4)  Fluorescent lamp
 * 5)  Incandescent light bulb (Level 4)
 * 6)  Neon lighting
 * 7)  Gas lighting
 * 8)  Gas mantle
 * 9)  Lantern
 * 10)  Oil lamp
 * 11)  Prism lighting
 * 12)  Light tube

Power generation

 * 1)  Power station (Level 4)
 * 2)  Electric generator (Level 4)
 * 3)  Induction generator
 * 4)  Electricity generation (Level 4)
 * 5)  Hydropower (Level 3)
 * 6)  Hydroelectricity (Level 4)
 * 7)  Tidal power
 * 8)  Watermill (Level 4)
 * 9)  Microgeneration
 * 10)  Micro-CHP
 * 11)  Nuclear power (Level 3)
 * 12)  Fusion power
 * 13)  Inertial confinement fusion
 * 14)  Tokamak
 * 15)  Nuclear reactor
 * 16)  Breeder reactor
 * 17)  Molten-salt reactor
 * 18)  Heavy water reactor
 * 19)  Small modular reactor
 * 20)  Nuclear marine propulsion
 * 21)  Nuclear meltdown
 * 22)   Solar energy (Level 3)
 * 23)   Solar power (Level 4)
 * 24)   Solar cell (Level 4)
 * 25)  Solar panel
 * 26)  Thermal power station
 * 27)  Boiler (power generation)
 * 28)  Cogeneration
 * 29)  Combined cycle power plant
 * 30)  Concentrated solar power
 * 31)  Cooling tower (Level 4)
 * 32)  Fossil fuel power station
 * 33)  Coal-fired power station
 * 34)  Gas-fired power plant
 * 35)  Geothermal power (Level 4)
 * 36)  Turbine (Level 4)
 * 37)  Gas turbine (Level 4)
 * 38)  Steam turbine (Level 4)
 * 39)  Wind turbine (Level 4)
 * 40)   Wind power (Level 3)
 * 41)   Windmill (Level 4)

Power storage

 * 1)  Energy storage
 * 2)  Electric battery (Level 3)
 * 3)  Lead-acid battery
 * 4)  Nickel–iron battery
 * 5)  Nickel–metal hydride battery
 * 6)  Lithium-ion battery
 * 7)  Lithium polymer battery
 * 8)  Alkaline battery
 * 9)  Atomic battery
 * 10)  Fuel cell
 * 11)  Pumped-storage hydroelectricity
 * 12)  Solar fuel

Power transmission
See also: Electromagnetism and Electromagnetism
 * 1)   AC power plugs and sockets
 * 2)  Electric power transmission (Level 4)
 * 3)  Electric power distribution (Level 4)
 * 4)  Electrical grid (Level 4)
 * 5)  Three-phase electric power
 * 6)  Virtual power plant
 * 7)  Electrical wiring (Level 4)
 * 8)  Electrical cable (Level 4)
 * 9)  Mains electricity

Concepts

 * 1)  Availability factor
 * 2)  Automatic generation control
 * 3)  Backfeeding
 * 4)  Base load
 * 5)  Capacity factor
 * 6)  Demand factor
 * 7)  Droop speed control
 * 8)  Energy demand management
 * 9)  Energy return on investment
 * 10)  Electrical fault
 * 11)  Grid energy storage
 * 12)  Grid code
 * 13)  Home energy storage
 * 14)  Load factor (electrical)
 * 15)  Load-following power plant
 * 16)  Merit order
 * 17)  Nameplate capacity
 * 18)  Peak demand
 * 19)  Electric power quality
 * 20)  Power-flow study
 * 21)  Repowering
 * 22)  Utility frequency
 * 23)  Variable renewable energy

Electricity transmission and distribution

 * 1)  Demand response
 * 2)  Distributed generation
 * 3)  Distribution board
 * 4)  Dynamic demand (electric power)
 * 5)  Electrical busbar system
 * 6)  Electric power system
 * 7)  Interconnector
 * 8)  High-voltage direct current
 * 9)  Load management
 * 10)  Electricity market
 * 11)  Mains electricity by country
 * 12)  Overhead power line
 * 13)  Smart grid
 * 14)  Electrical substation
 * 15)  Super grid
 * 16)  Transmission system operator
 * 17)  Transmission tower
 * 18)  Utility pole
 * 19)  Overhead cable
 * 20)  Wide area synchronous grid

Electrical protective devices

 * 1)  Arc-fault circuit interrupter
 * 2)  Circuit breaker (Level 4)
 * 3)  Earth-leakage circuit breaker
 * 4)  Fuse (electrical) (Level 4)
 * 5)   Lightning rod
 * 6)  Residual-current device
 * 7)  Power system protection
 * 8)  Protective relay
 * 9)  Numerical relay
 * 10)  Sulfur hexafluoride circuit breaker

Specific energy structure
See "Dams" section in "Specific infrastructure" for hydroelectric power plants
 * 1)  Synchronous grid of Continental Europe
 * 2)  Eastern Interconnection
 * 3)  Western Interconnection

=Industry =

See also: "Industry" in Business and economics (Level 4)

Industry: General

 * 1)  Factory (Level 4)
 * 2)  Assembly line (Level 4)
 * 3)  Automation (Level 4)
 * 4)  Conveyor system
 * 5)  Conveyor belt
 * 6)  Industrial robot (Level 4)
 * 7)  Interchangeable parts (Level 4)
 * 8)  Mass production (Level 4)
 * 9)  Mechanization (Level 4)
 * 10)  Pelletizing
 * 11)  Standardization (Level 4)
 * 12)  Waste (Level 4)
 * 13)  Incineration
 * 14)  Landfill (Level 4)
 * 15)  Recycling (Level 4)
 * 16)  Waste management (Level 4)
 * 17)  3D printing

Food, water and health

 * 1)  Air purifier
 * 2)  Air filter
 * 3)  HEPA
 * 4)  Catalytic converter
 * 5)  Respirator
 * 6)  Gas mask
 * 7)  Scrubber
 * 8)  Bleach (Level 4)
 * 9)  Desalination (Level 4)
 * 10)  Detergent (Level 4)
 * 11)  Laundry (Level 4)
 * 12)  Food processing
 * 13)  Fermentation in food processing
 * 14)  Pasteurization (Level 4)
 * 15)  Food storage
 * 16)  Oxygen mask
 * 17)  Sanitation (Level 3)
 * 18)  Sewage
 * 19)  Sanitary sewer (Level 4)
 * 20)  Sewage treatment (Level 4)
 * 21)  Septic tank
 * 22)  Water purification (Level 4)
 * 23)  Soap (Level 4)
 * 24)  Sterilization (microbiology)
 * 25)  Water supply network (Level 4)
 * 26)  Aqueduct (water supply) (Level 4)
 * 27)  Pumping station (Level 4)
 * 28)  Qanat (Level 4)
 * 29)  Water tower (Level 4)
 * 30)  Well (Level 4)

Materials

 * 1)  Abrasive (Level 4)
 * 2)  Ceramic (Level 4)
 * 3)  Pottery (Level 3)
 * 4)  Earthenware
 * 5)  Ironstone china
 * 6)  Lithophane
 * 7)  Porcelain (Level 4)
 * 8)  Stoneware
 * 9)  Terracotta
 * 10)  Kiln
 * 11)  Chemical vapor deposition
 * 12)  Cork (material)
 * 13)   Glass (Level 3)
 * 14)  Borosilicate glass
 * 15)  Float glass
 * 16)  Fused quartz
 * 17)  Glassblowing
 * 18)  Glass fiber
 * 19)  Glass wool
 * 20)  Safety glass
 * 21)  Soda–lime glass
 * 22)  Gutta-percha
 * 23)  Leather (Level 4)
 * 24)  Artificial leather
 * 25)  Hide (skin)
 * 26)  Liming (leather processing)
 * 27)  Parchment (Level 4)
 * 28)  Vellum
 * 29)  Suede
 * 30)  Tanning (leather)
 * 31)  Mineral wool
 * 32)  Natural rubber (Level 3)
 * 33)  Vulcanization
 * 34)  Paper (Level 3)
 * 35)  Cardboard
 * 36)  Papermaking
 * 37)  Pulp (paper)
 * 38)  Sizing
 * 39)  Papyrus (Level 4)
 * 40)  Tissue paper
 * 41)  Plastic (Level 3)
 * 42)  Carbon-fiber reinforced polymer
 * 43)  Fiberglass
 * 44)  Injection moulding
 * 45)  Microplastics

Chemicals

 * 1)  Adhesive (Level 4)
 * 2)  Chemical plant (Level 4)
 * 3)  Composite material (Level 4)
 * 4)  Explosive (Level 3)
 * 5)  Dynamite (Level 4)
 * 6)  Fireworks (Level 4)
 * 7)  Lubricant
 * 8)  Petrochemical (Level 4)

Metallurgy

 * 1)  Metallurgy (Level 3)
 * 2)  Smelting (Level 4)
 * 3)   Blast furnace
 * 4)  Crucible
 * 5)  Electric arc furnace
 * 6)  Induction furnace
 * 7)  Extractive metallurgy
 * 8)  Gold dredge
 * 9)  Mineral processing
 * 10)  Crusher
 * 11)  Mechanical screening
 * 12)  Spiral separator
 * 13)  Stamp mill
 * 14)  Trommel screen
 * 15)  Rocker box
 * 16)  Metalworking (Level 4)
 * 17)  Anvil
 * 18)  Bellows
 * 19)  Bending (metalworking)
 * 20)  Metal casting
 * 21)  Die casting (Level 4)
 * 22)  Lost-wax casting
 * 23)  Sand casting
 * 24)  Drawing (manufacturing)
 * 25)  Wire (Level 4)
 * 26)  Electrical discharge machining
 * 27)  Extrusion (Level 4)
 * 28)  Forge
 * 29)  Forging (Level 4)
 * 30)  Power hammer
 * 31)  Grinding (abrasive cutting)
 * 32)  Heat treating (Level 4)
 * 33)  Laser cutting (Level 4)
 * 34)  Machining
 * 35)  Metal fabrication
 * 36)  Plating
 * 37)  Anodizing
 * 38)  Electroplating
 * 39)  Powder coating
 * 40)  Precipitation hardening
 * 41)  Quenching
 * 42)  Rolling (metalworking) (Level 4)
 * 43)  Sheet metal
 * 44)  Sintering
 * 45)  Soldering (Level 4)
 * 46)  Steelmaking (Level 4)
 * 47)  Welding (Level 4)
 * 48)  Work hardening

Textiles

 * 1)  Textile (Level 3)
 * 2)  Carding

Fabrics and fibers

 * 1)  Canvas (Level 4)
 * 2)  Carbon fibers
 * 3)  Cotton (Level 3)
 * 4)  Chino cloth
 * 5)  Denim
 * 6)  Muslin
 * 7)  Felt (Level 4)
 * 8)  Flannel
 * 9)  Fiber (Level 4)
 * 10)  Jute (Level 4)
 * 11)  Kevlar
 * 12)  Lace (Level 4)
 * 13)  Linen (Level 4)
 * 14)  Polyester (Level 4)
 * 15)  Rayon
 * 16)  Silk (Level 4)
 * 17)  Spandex
 * 18)  Thread (yarn) (Level 4)
 * 19)  Wool (Level 4)
 * 20)  Cashmere wool
 * 21)  Tweed
 * 22)  Yarn (Level 4)

Other techniques

 * 1)  Basket weaving (Level 4)
 * 2)  Crochet (Level 4)
 * 3)  Dyeing (Level 4)
 * 4)  Dye (Level 4)
 * 5)  Embroidery (Level 4)
 * 6)  Knitting (Level 4)
 * 7)  Macramé
 * 8)  Textile printing
 * 9)  Quilting (Level 4)
 * 10)  Quilt
 * 11)  Sewing (Level 4)
 * 12)  Pattern

Spinning

 * 1)  Hand spinning (Level 4)
 * 2)  Distaff
 * 3)  Spindle (textiles)
 * 4)  Open-end spinning
 * 5)  Spinning (polymers)
 * 6)  Spinneret (polymers)
 * 7)  Ring spinning
 * 8)  Spinning frame
 * 9)  Water frame
 * 10)  Spinning jenny
 * 11)  Spinning mule
 * 12)  Spinning wheel

Weaving

 * 1)  Loom (Level 4)
 * 2)  Jacquard machine
 * 3)  Pirn
 * 4)  Power loom
 * 5)  Shuttle (weaving)
 * 6)  Flying shuttle
 * 7)  Weaving (Level 4)
 * 8)  Brocade
 * 9)  Damask
 * 10)  Plain weave
 * 11)  Satin
 * 12)  Songket
 * 13)  Tapestry (Level 4)
 * 14)  Twill
 * 15)  Warp and weft

=Infrastructure =

See also Arts: Architecture

Basics

 * 1)  Building (Level 3)
 * 2)  Infrastructure (Level 3)

Building materials

 * 1)  Brick (Level 4)
 * 2)  Fire brick
 * 3)  Cement (Level 4)
 * 4)  Bitumen
 * 5)  Portland cement
 * 6)  Concrete (Level 3)
 * 7)  Asphalt concrete
 * 8)  Concrete slab
 * 9)  Precast concrete
 * 10)  Prestressed concrete
 * 11)  Ready-mix concrete
 * 12)  Reinforced concrete
 * 13)  Rebar
 * 14)  Roman concrete
 * 15)  Shotcrete
 * 16)  Masonry (Level 3)
 * 17)  Brickwork
 * 18)  Stonemasonry
 * 19)  Quarry (Level 4)
 * 20)  Scaffolding (Level 4)
 * 21)  Adobe
 * 22)  Construction aggregate
 * 23)  Clapboard
 * 24)  Mortar (masonry)
 * 25)  Lath and plaster
 * 26)  Lath
 * 27)  Plaster
 * 28)  Drywall
 * 29)  Rammed earth
 * 30)  Roof shingle
 * 31)  Siding (construction)
 * 32)  Stone slab
 * 33)  Tile
 * 34)  Wattle and daub
 * 35)   Wood (Level 3)
 * 36)  Engineered wood
 * 37)  Wood–plastic composite
 * 38)  Lumber (Level 4)
 * 39)  Sawmill
 * 40)  Wood drying
 * 41)  Woodworking (Level 4)
 * 42)  Carpentry (Level 4)

Environmental remediation

 * 1)  Environmental remediation
 * 2)  Bioremediation
 * 3)  Bioaugmentation
 * 4)  Biostimulation
 * 5)  Phytoremediation
 * 6)  Groundwater remediation
 * 7)  In situ chemical oxidation
 * 8)  Soil vapor extraction
 * 9)  Remediation of contaminated sites with cement

Architectural elements

 * 1)  Arch (Level 4)
 * 2)  Buttress
 * 3)  Flying buttress
 * 4)  Ceiling (Level 4)
 * 5)  Column (Level 4)
 * 6)  Dome (Level 4)
 * 7)  Door (Level 4)
 * 8)  Elevator (Level 4)
 * 9)  Escalator
 * 10)  Façade (Level 4)
 * 11)  Floor (Level 4)
 * 12)  Foundation (engineering) (Level 4)
 * 13)  Ladder (Level 4)
 * 14)  Lighting (Level 4)
 * 15)  Pier (architecture)
 * 16)  Roof (Level 4)
 * 17)  Room (Level 4)
 * 18)  Stairs (Level 4)
 * 19)  Vault (architecture)
 * 20)  Wall (Level 4)
 * 21)  Window (Level 4)

Coastal infrastructure

 * 1)  Dock (Level 4)
 * 2)  Dry dock
 * 3)  Marina
 * 4)  Harbor (Level 4)
 * 5)  Lighthouse (Level 4)
 * 6)  Pier (Level 4)
 * 7)  Maritime passenger terminal
 * 8)  Port (Level 4)
 * 9)  Container port
 * 10)  Seawall

Ceremonial buildings

 * 1)  Pagoda (Level 4)
 * 2)  Pyramid (Level 4)

Commercial buildings

 * 1)  Convention center
 * 2)  Office (Level 4)
 * 3)  Warehouse (Level 4)

Mixed-use buildings

 * 1)  Tower block (Level 4)
 * 2)  Skyscraper (Level 4)
 * 3)  Tower (Level 4)

Residential buildings and housing units

 * 1)  Apartment (Level 4)
 * 2)  House (Level 4)
 * 3)  Hut (Level 4)
 * 4)  Igloo (Level 4)
 * 5)  Palace (Level 4)
 * 6)  Villa (Level 4)
 * 7)  Hotel (Level 4)
 * 8)  Inn
 * 9)  Motel
 * 10)  Hostel

Rooms and spaces

 * 1)  Attic
 * 2)  Balcony
 * 3)  Basement
 * 4)  Bathroom (Level 4)
 * 5)  Toilet (room)
 * 6)  Public toilet
 * 7)  Bedroom (Level 4)
 * 8)  Courtyard
 * 9)  Dining room
 * 10)  Garage (residential) (Level 4)
 * 11)  Hall
 * 12)   Kitchen (Level 4)
 * 13)  Laundry room
 * 14)  Living room
 * 15)  Lobby (room)
 * 16)  Porch
 * 17)  Patio
 * 18)  Sauna (Level 4)
 * 19)  Study (room)
 * 20)  Sunroom

Portable buildings and shelters

 * 1)  Tent (Level 4)
 * 2)  Yurt

Earthworks

 * 1)  Earthworks (engineering)
 * 2)  Trench
 * 3)  Undergrounding

Fire protection

 * 1)  Fire alarm system
 * 2)  Fire hydrant
 * 3)  Smoke detector

Hydraulic infrastructure

 * 1)  Cistern
 * 2)  Dam (Level 3)
 * 3)  Caisson (engineering)
 * 4)  Drainage (Level 4)
 * 5)  Sluice
 * 6)  Dredging
 * 7)  Flood control (Level 4)
 * 8)  Flood control in the Netherlands (Level 4)
 * 9)  Levee (Level 4)
 * 10)  Reservoir (Level 4)

Transport infrastructure
See also #Transportation section
 * 1)  Bridge (Level 3)
 * 2)  Cantilever bridge
 * 3)  Drawbridge
 * 4)  Flying junction
 * 5)  Pontoon bridge
 * 6)  Suspension bridge
 * 7)  Viaduct
 * 8)  Tunnel (Level 4)
 * 9)  Underwater tunnel
 * 10)  Tunnel construction
 * 11)  New Austrian tunneling method
 * 12)  Tunnel boring machine

Specific infrastructure
See "Transportation" and "Energy" section for infrastructure in respective discipline

Dams

 * 1)  Aswan Dam (Level 4)
 * 2)   Grand Coulee Dam
 * 3)  Grand Ethiopian Renaissance Dam
 * 4)  Hoover Dam (Level 4)
 * 5)  Itaipu Dam (Level 4)
 * 6)  Tarbela Dam
 * 7)  Three Gorges Dam (Level 4)
 * 8)  Akosombo Dam
 * 9)  Atatürk Dam
 * 10)  Bratsk Hydroelectric Power Station
 * 11)  Cahora Bassa
 * 12)  Cofferdam
 * 13)  New Croton Dam
 * 14)  Delta Works
 * 15)  Tabqa Dam
 * 16)  Fort Peck Dam
 * 17)  Grande Dixence Dam
 * 18)  Guri Dam
 * 19)  Enguri Dam
 * 20)  Kariba Dam
 * 21)  Mangla Dam
 * 22)  Nurek Dam
 * 23)  Oroville Dam
 * 24)  Rogun Dam
 * 25)  Sup'ung Dam
 * 26)  Vajont Dam

Bridges

 * 1)  Akashi Kaikyo Bridge (Level 4)
 * 2)  Alcántara Bridge
 * 3)  Astoria–Megler Bridge
 * 4)  Auckland Harbour Bridge
 * 5)  Banpo Bridge
 * 6)  Bosphorus Bridge
 * 7)  Bridge of Sighs
 * 8)  Bridge of the Americas
 * 9)  Britannia Bridge
 * 10)  Brooklyn Bridge (Level 4)
 * 11)  Charles Bridge
 * 12)  Confederation Bridge
 * 13)  Danyang–Kunshan Grand Bridge
 * 14)  El Ferdan Railway Bridge
 * 15)  Forth Bridge
 * 16)  Gateshead Millennium Bridge
 * 17)  George Washington Bridge
 * 18)  Golden Gate Bridge (Level 4)
 * 19)  Great Belt Bridge
 * 20)  Great Seto Bridge
 * 21)  Humber Bridge
 * 22)  Qingdao Jiaozhou Bay Bridge
 * 23)  Kapellbrücke
 * 24)  London Bridge
 * 25)  Mackinac Bridge
 * 26)  Manhattan Bridge
 * 27)  Mehmed Paša Sokolović Bridge
 * 28)  Menai Bridge
 * 29)  Millau Viaduct
 * 30)  Minneapolis Skyway System
 * 31)  Pont Alexandre III
 * 32)  Pont du Gard
 * 33)  Pont Neuf
 * 34)  Ponte Sant'Angelo
 * 35)  Ponte Vecchio
 * 36)  Rainbow Bridge (Niagara Falls)
 * 37)  Rainbow Bridge (Tokyo)
 * 38)  Rialto Bridge
 * 39)   San Francisco–Oakland Bay Bridge
 * 40)  Si-o-se-pol
 * 41)  Stari Most
 * 42)  Sydney Harbour Bridge
 * 43)  Tacoma Narrows Bridge
 * 44)  The Iron Bridge
 * 45)  Tower Bridge (Level 4)
 * 46)  Trajan's Bridge
 * 47)  Vasco da Gama Bridge
 * 48)  Verrazzano-Narrows Bridge

Tunnels

 * 1)  Channel Tunnel (Level 4)
 * 2)  Gotthard Base Tunnel
 * 3)  Seikan Tunnel

Multi-modal crossings

 * 1)  Bering Strait crossing
 * 2)  Chesapeake Bay Bridge–Tunnel
 * 3)  Hong Kong–Zhuhai–Macau Bridge
 * 4)  Tokyo Bay Aqua-Line
 * 5)  Øresund Bridge

Others

 * 1)  Multilevel streets in Chicago
 * 2)  List of international submarine communications cables

=Machinery and tools =

Machinery and tools: General

 * 1)  Machine (Level 4)
 * 2)  MEMS
 * 3)  Micromachinery
 * 4)  Nanoelectromechanical systems
 * 5)  Robotics (Level 3)
 * 6)  Android (robot)
 * 7)  Automaton
 * 8)   Robot (Level 4)
 * 9)  Robotic arm
 * 10)  Leg mechanism

Engines

 * 1)  Engine (Level 3)
 * 2)  Electric motor (Level 3)
 * 3)  Internal combustion engine (Level 3)
 * 4)  Diesel engine (Level 4)
 * 5)  Petrol engine
 * 6)  Reciprocating engine
 * 7)  Four-stroke engine (Level 4)
 * 8)  Two-stroke engine
 * 9)  Pistonless rotary engine
 * 10)  Wankel engine
 * 11)  Steam engine (Level 3)

Hydraulics and pneumatics

 * 1)  Hydraulics
 * 2)  Hydraulic cylinder
 * 3)  Hydraulic machinery
 * 4)  Hydraulic motor
 * 5)  Hydraulic manifold
 * 6)  Pump
 * 7)  Hydraulic ram
 * 8)  Siphon (Level 4)
 * 9)  Pipe (fluid conveyance) (Level 4)
 * 10)  Gasket (Level 4)
 * 11)  Valve (Level 4)
 * 12)  Plumbing (Level 4)
 * 13)  Bidet
 * 14)  Sink (Level 4)
 * 15)  Toilet (Level 4)
 * 16)  Flush toilet
 * 17)  Portable toilet
 * 18)  Squat toilet
 * 19)  Toilet seat
 * 20)  Urinal
 * 21)  Pneumatics
 * 22)  Compressor
 * 23)  Jackhammer
 * 24)  Nail gun
 * 25)  Rivet gun
 * 26)  Vacuum pump

Farm and garden machinery

 * 1)  Baler
 * 2)  Chainsaw (Level 4)
 * 3)  Combine harvester (Level 4)
 * 4)  Corn harvester
 * 5)  Cotton gin (Level 4)
 * 6)  Cotton picker
 * 7)  Cultivator (Level 4)
 * 8)  Irrigation sprinkler (Level 4)
 * 9)  Lawn mower (Level 4)
 * 10)  Planter (farm implement)
 * 11)  Reaper
 * 12)  Reaper-binder
 * 13)  Seed drill
 * 14)  Swather
 * 15)  Threshing machine
 * 16)  Transplanter

Household appliances

 * 1)  Home appliance (Level 4)
 * 2)  Major appliance
 * 3)  Barbecue grill
 * 4)  Blender
 * 5)  Clothes dryer (Level 4)
 * 6)  Coffeemaker
 * 7)  Dishwasher (Level 4)
 * 8)  Furnace (central heating) (Level 4)
 * 9)  Hair dryer
 * 10)  Hair iron
 * 11)  Humidifier
 * 12)  Ironing (Level 4)
 * 13)  Juicer
 * 14)  Lock and key (Level 4)
 * 15)  Dead bolt
 * 16)  Disc tumbler lock
 * 17)  Electronic lock
 * 18)  Lever tumbler lock
 * 19)  Pin tumbler lock
 * 20)  Skeleton key
 * 21)  Microwave oven (Level 4)
 * 22)  Cavity magnetron (Level 4)
 * 23)  Mixer (appliance)
 * 24)  Oven (Level 3)
 * 25)  Convection oven
 * 26)  Refrigerator (Level 4)
 * 27)  Rice cooker
 * 28)  Sewing machine (Level 4)
 * 29)  Slow cooker
 * 30)  Stove (Level 4)
 * 31)  Electric stove
 * 32)  Vacuum cleaner (Level 4)
 * 33)  Washing machine (Level 4)
 * 34)  Water dispenser
 * 35)  Water heating

Industrial machinery

 * 1)  Centrifuge (Level 4)
 * 2)  Ultracentrifuge
 * 3)  Crane (machine) (Level 4)
 * 4)  Forklift
 * 5)  Mill (grinding)
 * 6)  Machine tool
 * 7)  Lathe (Level 4)
 * 8)  Machine press (Level 4)
 * 9)  Milling (machining)
 * 10)  Numerical control
 * 11)  Potter's wheel (Level 4)
 * 12)  Trip hammer

Mechanisms

 * 1)  Mechanism (engineering)

Flexible components

 * 1)  Belt (mechanical)
 * 2)  Chain (Level 4)
 * 3)  Net (device)
 * 4)  Mesh
 * 5)  Sieve
 * 6)  Rope (Level 4)
 * 7)  Knot (Level 4)
 * 8)  List of knots
 * 9)  Bowline
 * 10)  Double fisherman's knot
 * 11)  Figure-eight knot
 * 12)  Wire rope
 * 13)  Bowden cable
 * 14)  Flexible shaft
 * 15)  Spring (device) (Level 4)

Rigid components

 * 1)  Blade
 * 2)  Fastener (Level 4)
 * 3)  Nail (fastener) (Level 4)
 * 4)  Nut (hardware) (Level 4)
 * 5)  Rivet (Level 4)
 * 6)  Screw
 * 7)  Washer (hardware) (Level 4)
 * 8)  Gear (Level 4)
 * 9)  Hook
 * 10)  Piston
 * 11)  Simple machine (Level 3)
 * 12)  Inclined plane (Level 4)
 * 13)  Lever (Level 4)
 * 14)  Pulley (Level 4)
 * 15)  Block and tackle
 * 16)  Screw mechanism (Level 4)
 * 17)  Propeller
 * 18)  Wedge (Level 4)
 * 19)  Wheel (Level 3)
 * 20)  Flywheel

Simple mechanisms

 * 1)  Kinematic pair
 * 2)  Ball joint
 * 3)  Bearing (mechanical) (Level 4)
 * 4)  Cam follower
 * 5)  Tappet
 * 6)  Hinge
 * 7)  Rack and pinion
 * 8)  Ratchet (device)
 * 9)  Rod end bearing
 * 10)  Wheel and axle (Level 4)
 * 11)  Axle (Level 4)
 * 12)  Linkage (mechanical)
 * 13)  Clutch (Level 4)
 * 14)  Differential (mechanical device)
 * 15)  Epicyclic gearing
 * 16)  Escapement
 * 17)  Four-bar linkage
 * 18)  Gimbal
 * 19)  Pantograph
 * 20)  Whippletree (mechanism)
 * 21)  Shock absorber
 * 22)  Dashpot
 * 23)  Winch
 * 24)  Capstan (nautical)
 * 25)  Windlass

Tools

 * 1)  Tool (Level 2)
 * 2)  Lifting equipment
 * 3)  Hoist (device)
 * 4)  Jack (device)

Agricultural tools

 * 1)  Archimedes' screw (Level 4)
 * 2)  Flail
 * 3)  Harrow (tool) (Level 4)
 * 4)  Hoe (tool) (Level 4)
 * 5)  Machete (Level 4)
 * 6)  Mattock
 * 7)  Pitchfork
 * 8)  Plough (Level 4)
 * 9)  Rake (tool) (Level 4)
 * 10)  Roller (agricultural tool)
 * 11)  Scythe
 * 12)  Sickle (Level 4)
 * 13)  Shadoof
 * 14)  Shovel (Level 4)

Artist's and drafting tools

 * 1)  Compass (drawing tool)
 * 2)  Drafting machine
 * 3)  Drawing board
 * 4)  Easel
 * 5)  Eraser
 * 6)  French curve
 * 7)  Ink (Level 4)
 * 8)  Modelling clay (Level 4)
 * 9)  Paint (Level 4)
 * 10)  Acrylic paint
 * 11)  Enamel paint
 * 12)  Varnish
 * 13)  Brush (Level 4)
 * 14)  Pastel (Level 4)
 * 15)  Pencil (Level 4)
 * 16)  Pencil sharpener
 * 17)   Pigment (Level 4)
 * 18)  Pen (Level 4)
 * 19)  Ballpoint pen
 * 20)  T-square

Containers

 * 1)  Container (Level 4)
 * 2)  Aluminum can
 * 3)  Bag
 * 4)  Paper bag
 * 5)  Plastic bag
 * 6)  Barrel
 * 7)  Basket
 * 8)  Bottle
 * 9)  Water bottle
 * 10)  Box
 * 11)  Cardboard box
 * 12)  Coffin
 * 13)  Crate
 * 14)  Wooden box
 * 15)  Envelope
 * 16)  Intermodal container
 * 17)  Packaging
 * 18)  Paper cup
 * 19)  Pressure vessel
 * 20)  Steel and tin cans

Hand tools

 * 1)  Adze
 * 2)  Axe (Level 4)
 * 3)  Chalk line
 * 4)  Chisel (Level 4)
 * 5)  Clamp (tool) (Level 4)
 * 6)  Crowbar
 * 7)  Drilling (Level 4)
 * 8)  Hammer (Level 4)
 * 9)  Hook (hand tool)
 * 10)  Plane (tool) (Level 4)
 * 11)  Pliers
 * 12)  Saw (Level 4)
 * 13)  Scissors (Level 4)
 * 14)  Screwdriver
 * 15)  Wrench

Measuring instruments

 * 1)  Instrumentation (Level 4)
 * 2)  Barometer (Level 4)
 * 3)  Calipers (Level 4)
 * 4)  Feeler gauge
 * 5)  Ruler (Level 4)
 * 6)  Meterstick
 * 7)  Tape measure
 * 8)  Photometer (Level 4)
 * 9)  Spectrometer (Level 4)
 * 10)  Optical spectrometer
 * 11)  Thermometer (Level 4)
 * 12)  Astrolabe
 * 13)  Breathalyzer
 * 14)  Calorimeter
 * 15)  Geiger counter
 * 16)  Odometer
 * 17)  Seismometer
 * 18)  Speedometer
 * 19)  Torque wrench
 * 20)  Vernier scale
 * 21)  Polygraph

Surveying tools

 * 1)  Alidade
 * 2)  Circumferentor
 * 3)  Graphometer
 * 4)  Gunter's chain
 * 5)  Laser rangefinder
 * 6)  Lidar
 * 7)  Level (optical instrument)
 * 8)  Inclinometer
 * 9)  Topographic Abney level
 * 10)  Level staff
 * 11)  Plumb bob
 * 12)  Spirit level
 * 13)  Tiltmeter
 * 14)  Plane table
 * 15)  Reticle
 * 16)  Stadimeter
 * 17)  Stadia mark
 * 18)  Surveyor's wheel
 * 19)  Theodolite (Level 4)
 * 20)  Total station

=Medical technology =

Diagnostic technologies

 * 1)  DNA profiling (Level 4)
 * 2)  Electrocardiography (Level 4)
 * 3)  Electroencephalography
 * 4)  Endoscopy (Level 4)

Imaging

 * 1)  Medical imaging (Level 3)
 * 2)  CT scan
 * 3)  Magnetic resonance imaging (Level 4)
 * 4)  Medical ultrasound (Level 4)
 * 5)  Positron emission tomography
 * 6)  Radiography (Level 4)

Devices

 * 1)  Artificial cardiac pacemaker
 * 2)  Artificial organ (Level 4)
 * 3)  Hearing aid
 * 4)  Prosthesis (Level 4)
 * 5)  Reflex hammer
 * 6)  Sling (medicine)
 * 7)  Splint (medicine)
 * 8)  Stethoscope (Level 4)
 * 9)  Tourniquet
 * 10)  Ventilator
 * 11)  Wheelchair (Level 4)

Equipment

 * 1)  Adhesive bandage
 * 2)  Bandage (Level 4)
 * 3)  Hypodermic needle
 * 4)  Retainer (orthodontics)
 * 5)  Stretcher
 * 6)  Syringe (Level 4)

Techniques

 * 1)  Cardiopulmonary bypass (Level 4)
 * 2)  Dialysis (chemistry) (Level 4)

Transport

 * 1)   Ambulance (Level 4)
 * 2)  Air medical services

=Military technology =

Military technology: General

 * 1)  Weapon (Level 3)
 * 2)  Military technology (Level 4)
 * 3)  Booby trap
 * 4)  Punji stick
 * 5)  Trou de loup
 * 6)  Siege engine
 * 7)  Battering ram (Level 4)
 * 8)  Siege tower

Countermeasures

 * 1)  Stealth technology (Level 4)
 * 2)  Missile defense

Armour

 * 1)  Armour (Level 3)
 * 2)  Body armor
 * 3)  Bulletproof vest (Level 4)
 * 4)  Chain mail (Level 4)
 * 5)  Plate armour (Level 4)
 * 6)  Vehicle armour
 * 7)  Reactive armour
 * 8)  Helmet (Level 4)
 * 9)  Combat helmet
 * 10)  Shield (Level 4)
 * 11)  Scutum

Fortification

 * 1)  Fortification (Level 3)
 * 2)  Bastion fort
 * 3)  Glacis
 * 4)  Ravelin
 * 5)  Tenaille
 * 6)  Castle (Level 4)
 * 7)  Motte-and-bailey castle
 * 8)  Bastion
 * 9)  Curtain wall (fortification)
 * 10)  Gatehouse
 * 11)  Keep
 * 12)  Defensive wall (Level 4)
 * 13)  Palisade
 * 14)  Rampart (fortification)

Melee weapons

 * 1)  Melee weapon
 * 2)  Battle axe (Level 4)
 * 3)  Brass knuckles
 * 4)  Club (weapon) (Level 4)
 * 5)  Baton (law enforcement)
 * 6)  Mace (bludgeon)
 * 7)  War hammer
 * 8)  Flail (weapon)
 * 9)  Nunchaku
 * 10)  Sai (weapon)
 * 11)  Tonfa

Knives

 * 1)  Bayonet (Level 4)
 * 2)  Knife (Level 3)
 * 3)  Dagger (Level 4)
 * 4)  Bowie knife
 * 5)  Hunting knife
 * 6)  Pocketknife
 * 7)  Swiss Army knife
 * 8)  Switchblade
 * 9)  Throwing knife
 * 10)  Utility knife

Polearms

 * 1)  Polearm
 * 2)  Dagger-axe
 * 3)  Ji (polearm)
 * 4)  Halberd
 * 5)  Naginata
 * 6)  Partisan (weapon)
 * 7)  Spear (Level 4)
 * 8)  Pike (weapon)

Swords

 * 1)  Sword (Level 4)
 * 2)  Claymore
 * 3)  Cutlass
 * 4)  Dao (Chinese sword)
 * 5)  Gladius
 * 6)  Katana (Level 4)
 * 7)  Longsword
 * 8)  Rapier (Level 4)
 * 9)  Sabre
 * 10)  Scimitar
 * 11)  Talwar
 * 12)  Wakizashi

Ranged weapons

 * 1)  Ranged weapon
 * 2)  Boomerang (Level 4)
 * 3)  Javelin
 * 4)  Spear-thrower
 * 5)  Shuriken
 * 6)  Sling (weapon) (Level 4)
 * 7)  Slingshot

Archery

 * 1)  Bow and arrow (Level 3)
 * 2)  Compound bow
 * 3)  Longbow
 * 4)  Recurve bow
 * 5)  Arrow
 * 6)  Arrowhead
 * 7)  Fletching
 * 8)  Bowstring
 * 9)   Crossbow (Level 4)
 * 10)  Repeating crossbow
 * 11)  Quiver

Artillery

 * 1)  Artillery (Level 4)
 * 2)  Cannon (Level 4)
 * 3)  Field gun
 * 4)  Howitzer
 * 5)  Limbers and caissons
 * 6)  Mortar (weapon) (Level 4)
 * 7)  Catapult (Level 4)
 * 8)  Ballista (Level 4)
 * 9)  Polybolos
 * 10)  Mangonel
 * 11)  Onager (weapon)
 * 12)  Trebuchet
 * 13)  Railgun

Firearms

 * 1)  Firearm (Level 3)
 * 2)  Fire lance
 * 3)  Hand cannon
 * 4)  Gun
 * 5)  Handgun (Level 4)
 * 6)  Revolver
 * 7)  Pistol
 * 8)  Long gun
 * 9)  Arquebus
 * 10)  Musket (Level 4)
 * 11)  Rifle (Level 4)
 * 12)  Assault rifle (Level 4)
 * 13)  Sniper rifle
 * 14)  Shotgun (Level 4)
 * 15)  Submachine gun
 * 16)  Machine gun (Level 4)
 * 17)  Autocannon
 * 18)  Rotary cannon

Ammunition

 * 1)  Ammunition (Level 4)
 * 2)  Ammunition box
 * 3)  Gunpowder (Level 3)
 * 4)  Powder keg
 * 5)  Smokeless powder
 * 6)  Bullet
 * 7)  Armor-piercing bullet
 * 8)  Hollow-point bullet
 * 9)  Tracer ammunition
 * 10)  Flechette
 * 11)  Cartridge (firearms)
 * 12)  Sabot (firearms)
 * 13)  Shotgun cartridge
 * 14)  Shot (pellet)
 * 15)  Shotgun slug

Mechanisms

 * 1)  Breechloader
 * 2)  Action (firearms)
 * 3)  Automatic firearm
 * 4)  Bolt action
 * 5)  Burst mode (weapons)
 * 6)  Repeating firearm
 * 7)  Selective fire
 * 8)  Semi-automatic firearm
 * 9)  Firing pin
 * 10)  Magazine (firearms)
 * 11)  Gun barrel
 * 12)  Multiple-barrel firearm
 * 13)  Rifling
 * 14)  Muzzleloader
 * 15)  Flintlock
 * 16)  Matchlock
 * 17)  Percussion cap
 * 18)  Wheellock
 * 19)  Trigger (firearms)

Specific cartridges

 * 1)  9×19mm Parabellum
 * 2)  5.56×45mm NATO

Specific firearms

 * 1)   AK-47
 * 2)  AR-15–style rifle
 * 3)  Chassepot
 * 4)  Dreyse needle gun
 * 5)  Gatling gun
 * 6)  Glock
 * 7)  IWI Tavor
 * 8)  M134 Minigun
 * 9)  M4 carbine
 * 10)   M16 rifle
 * 11)  M1911 pistol

Missiles

 * 1)  Missile (Level 4)
 * 2)  Air-to-air missile
 * 3)  Anti-tank guided missile
 * 4)  Cruise missile
 * 5)  Intercontinental ballistic missile
 * 6)  Rocket-propelled grenade
 * 7)  Surface-to-air missile
 * 8)  Man-portable air-defense system
 * 9)  Missile guidance
 * 10)  Multiple rocket launcher
 * 11)  Warhead

Explosive weapons

 * 1)  Bomb (Level 3)
 * 2)  Improvised explosive device (Level 4)
 * 3)  Car bomb
 * 4)  Detonator
 * 5)  Fuze
 * 6)  Contact fuze
 * 7)  Proximity fuze
 * 8)  Cluster munition (Level 4)
 * 9)  Grenade (Level 4)
 * 10)  Land mine (Level 4)
 * 11)  Plastic explosive
 * 12)  Shaped charge
 * 13)  Explosively formed penetrator
 * 14)  High-explosive anti-tank
 * 15)  Thermobaric weapon

Incendiary weapons

 * 1)  Greek fire
 * 2)  Flamethrower
 * 3)  Molotov cocktail
 * 4)  Napalm (Level 4)
 * 5)   White phosphorus munitions

Maneuver

 * 1)   Horses in warfare (Level 4)
 * 2)  Caltrop
 * 3)  Chariot (Level 4)
 * 4)  Infantry fighting vehicle
 * 5)  Armoured personnel carrier
 * 6)  Technical (vehicle)
 * 7)   Tank (Level 4)
 * 8)  Main battle tank
 * 9)   War elephant (Level 4)

Military aviation

 * 1)  Military aviation
 * 2)  Military aircraft (Level 4)
 * 3)  Military glider
 * 4)  Military helicopter
 * 5)  Attack aircraft (Level 4)
 * 6)  Gunship
 * 7)  Bomber (Level 4)
 * 8)  Strategic bomber
 * 9)  Heavy bomber
 * 10)  Medium bomber
 * 11)  Interdictor
 * 12)  Penetrator (aircraft)
 * 13)  Fighter aircraft (Level 4)
 * 14)  Air superiority fighter
 * 15)  Interceptor aircraft
 * 16)  Fighter-bomber
 * 17)  Strike fighter
 * 18)  Electronic-warfare aircraft
 * 19)  Maritime patrol aircraft
 * 20)  Multirole combat aircraft
 * 21)  Military transport aircraft
 * 22)  Airborne early warning and control
 * 23)  Reconnaissance aircraft
 * 24)  Surveillance aircraft
 * 25)  Experimental aircraft
 * 26)  Aerial refueling

Specific aircraft

 * 1)  Boeing B-29 Superfortress
 * 2)  Enola Gay
 * 3)   Boeing B-52 Stratofortress
 * 4)  Dassault Rafale
 * 5)  Embraer EMB 314 Super Tucano
 * 6)  Eurofighter Typhoon
 * 7)  Fairchild Republic A-10 Thunderbolt II
 * 8)   General Dynamics F-16 Fighting Falcon
 * 9)  Lockheed C-130 Hercules
 * 10)   Lockheed SR-71 Blackbird
 * 11)  Lockheed Martin F-22 Raptor
 * 12)   Lockheed Martin F-35 Lightning II
 * 13)  McDonnell Douglas F-15 Eagle
 * 14)  McDonnell Douglas F/A-18 Hornet
 * 15)  Mikoyan-Gurevich MiG-21
 * 16)  North American P-51 Mustang
 * 17)  Northrop B-2 Spirit
 * 18)  Panavia Tornado
 * 19)  Rockwell B-1 Lancer

Naval warfare

 * 1)  Warship (Level 4)
 * 2)   Aircraft carrier (Level 4)
 * 3)  Battleship (Level 4)
 * 4)  Dreadnought
 * 5)  Corvette
 * 6)  Cruiser
 * 7)  Destroyer
 * 8)  Frigate
 * 9)  Galleon
 * 10)  Galley (Level 4)
 * 11)  Trireme
 * 12)  Gunboat
 * 13)   Ironclad warship
 * 14)  Ship of the line (Level 4)
 * 15)   Submarine (Level 4)
 * 16)  Boom (navigational barrier)
 * 17)  Anti-submarine net
 * 18)  Depth charge
 * 19)  Naval mine (Level 4)
 * 20)  Torpedo (Level 4)

Less-lethal weapons

 * 1)  Non-lethal weapon
 * 2)  Active Denial System
 * 3)  Baton round
 * 4)  Bean bag round
 * 5)  Plastic bullet
 * 6)  Rubber bullet
 * 7)  Sponge grenade
 * 8)  Sonic weapon
 * 9)  Stun grenade
 * 10)  Taser
 * 11)  Tear gas
 * 12)  CS gas
 * 13)  Pepper spray
 * 14)  Water cannon

Weapon of mass destruction

 * 1)  Weapon of mass destruction (Level 4)
 * 2)  Biological warfare (Level 4)
 * 3)  Entomological warfare
 * 4)  Chemical weapon (Level 4)
 * 5)  Blister agent
 * 6)  Blood agent
 * 7)  Nerve agent
 * 8)  Dirty bomb
 * 9)   Nuclear weapon (Level 4)
 * 10)  Thermonuclear weapon (Level 4)
 * 11)  Nuclear weapon design
 * 12)  Nuclear proliferation

=Navigation and timekeeping =

For units of time (hour, day, etc.), see Physical sciences – Measurement. For maps and cartography, see Geography – Physical geography.

Navigation

 * 1)  Navigation (Level 3)
 * 2)  Compass (Level 3)
 * 3)  Cardinal direction (Level 4)
 * 4)  North
 * 5)  South
 * 6)  East
 * 7)  West
 * 8)  Celestial navigation (Level 4)
 * 9)  Backstaff
 * 10)  Jacob's staff
 * 11)  Octant (instrument)
 * 12)  Quadrant (instrument)
 * 13)  Sextant (Level 4)
 * 14)  Dead reckoning (Level 4)
 * 15)  Gyroscope (Level 4)
 * 16)  Satellite navigation (Level 4)
 * 17)  BeiDou
 * 18)  Galileo (satellite navigation)
 * 19)  Global Positioning System (Level 4)
 * 20)  GLONASS
 * 21)  Satellite navigation device
 * 22)   Radar (Level 3)
 * 23)  Sonar

Timekeeping

 * 1)  Astronomical year numbering
 * 2)  Calendar (Level 3)
 * 3)  Clock (Level 3)
 * 4)  Leap year (Level 4)
 * 5)  Leap second
 * 6)  Future
 * 7)  Present
 * 8)  Past
 * 9)  Standard time
 * 10)  Timeline
 * 11)  Time standard
 * 12)  Coordinated Universal Time (Level 4)
 * 13)  Greenwich Mean Time
 * 14)  International Atomic Time
 * 15)  Time zone (Level 4)
 * 16)   Daylight saving time (Level 4)

Calendars

 * 1)  Solar calendar
 * 2)  Gregorian calendar (Level 4)
 * 3)   Anno Domini
 * 4)  Common Era
 * 5)  Julian calendar (Level 4)
 * 6)  Lunisolar calendar
 * 7)  Buddhist calendar
 * 8)  Chinese calendar (Level 4)
 * 9)  Hindu calendar
 * 10)  Lunar calendar
 * 11)   Hebrew calendar
 * 12)  Islamic calendar (Level 4)

Clocks

 * 1)  12-hour clock
 * 2)  24-hour clock
 * 3)  Alarm clock
 * 4)  Atomic clock (Level 4)
 * 5)  Digital clock
 * 6)  Clock face
 * 7)  Hourglass
 * 8)  Marine chronometer
 * 9)  Pendulum clock
 * 10)  Pendulum (Level 4)
 * 11)  Quartz clock
 * 12)  Sundial (Level 4)
 * 13)  Watch (Level 4)
 * 14)  Pocket watch
 * 15)  Stopwatch
 * 16)  Water clock

Months

 * 1)  January
 * 2)  February
 * 3)  March
 * 4)  April
 * 5)  May
 * 6)  June
 * 7)  July
 * 8)  August
 * 9)  September
 * 10)  October
 * 11)  November
 * 12)  December

Days of the Week

 * 1)  Names of the days of the week
 * 2)  Sunday
 * 3)  Monday
 * 4)  Tuesday
 * 5)  Wednesday
 * 6)  Thursday
 * 7)  Friday
 * 8)  Saturday

=Optical technology =

Optical components

 * 1)  Lens (Level 3)
 * 2)  Fresnel lens
 * 3)  Thin lens
 * 4)  Anti-reflective coating (Level 4)
 * 5)  Collimator
 * 6)  Diffraction grating (Level 4)
 * 7)  Mirror (Level 4)
 * 8)  One-way mirror
 * 9)   Optical fiber (Level 4)
 * 10)  Optical filter
 * 11)  Optical isolator
 * 12)  Polarizer (Level 4)
 * 13)  Prism (optics) (Level 4)
 * 14)  Pentaprism

Optical instruments

 * 1)  Autocollimator
 * 2)  Binoculars (Level 4)
 * 3)   Glasses (Level 4)
 * 4)  Bifocals
 * 5)   Contact lens
 * 6)  Interferometry (Level 4)
 * 7)  Loupe
 * 8)  Magnifying glass
 * 9)  Microscope (Level 3)
 * 10)  Electron microscope (Level 4)
 * 11)  Scanning electron microscope
 * 12)  Transmission electron microscopy
 * 13)  Scanning tunneling microscope
 * 14)  Optical microscope (Level 4)
 * 15)  Periscope
 * 16)  Projector

Lasers

 * 1)  Laser (Level 3)
 * 2)  Solid-state laser
 * 3)  Ruby laser
 * 4)  YAG laser
 * 5)  Dye laser
 * 6)  Gas laser
 * 7)  Carbon-dioxide laser
 * 8)  Helium–neon laser
 * 9)  Maser

Photography

 * 1)  Camera (Level 3)
 * 2)  Hidden camera
 * 3)  Instant camera
 * 4)  Rangefinder camera
 * 5)  Single-lens reflex camera
 * 6)  Digital single-lens reflex camera
 * 7)  Twin-lens reflex camera
 * 8)  Closed-circuit television
 * 9)  Holography (Level 4)
 * 10)  Photographic film (Level 4)
 * 11)  Photographic plate
 * 12)  Photography (Level 3)
 * 13)  Digital photography (Level 4)
 * 14)  Fine-art photography (Level 4)
 * 15)  Landscape photography
 * 16)  Portrait photography
 * 17)  Street photography
 * 18)  Exposure (photography)
 * 19)  Flash (photography)
 * 20)  Multi-exposure HDR capture

= Astronomical technology =


 * 1)  Astronomical catalog
 * 2)  Ephemeris
 * 3)  Star chart
 * 4)  Astronomical Almanac

Telescope

 * 1)  Telescope (Level 3)
 * 2)  Reflecting telescope
 * 3)  Cassegrain reflector
 * 4)  Dobsonian telescope
 * 5)  Gregorian telescope
 * 6)  Newtonian telescope
 * 7)  Ritchey–Chrétien telescope
 * 8)  Schmidt–Cassegrain telescope
 * 9)  Refracting telescope
 * 10)  X-ray telescope
 * 11)  Optical telescope (Level 4)
 * 12)  Infrared telescope
 * 13)  Radio telescope (Level 4)
 * 14)  Solar telescope
 * 15)  Space telescope
 * 16)  Astronomical interferometer
 * 17)  Aperture synthesis
 * 18)  Telescope mount
 * 19)  Altazimuth mount
 * 20)  Equatorial mount
 * 21)  Active optics
 * 22)  Adaptive optics
 * 23)  Eyepiece
 * 24)  Astronomical filter
 * 25)  Primary mirror
 * 26)  Gravitational-wave observatory

Space-based observatories

 * 1)  Hubble Space Telescope (Level 4)
 * 2)  Spitzer Space Telescope
 * 3)  Herschel Space Observatory
 * 4)  INTEGRAL
 * 5)  Fermi Gamma-ray Space Telescope
 * 6)  James Webb Space Telescope
 * 7)  Wide-field Infrared Survey Explorer
 * 8)  IRAS
 * 9)  Chandra X-ray Observatory
 * 10)  Kepler
 * 11)  GALEX
 * 12)  Hipparcos
 * 13)  Gaia (spacecraft)
 * 14)  XMM-Newton
 * 15)  ROSAT

Ground-based observatories

 * 1)  Atacama Large Millimeter Array (Level 4)
 * 2)  Mauna Kea Observatories (Level 4)
 * 3)  Subaru Telescope
 * 4)  Thirty Meter Telescope
 * 5)  W. M. Keck Observatory
 * 6)  Gemini Observatory
 * 7)  Five-hundred-meter Aperture Spherical Telescope
 * 8)  LIGO
 * 9)  Virgo interferometer
 * 10)  IceCube Neutrino Observatory
 * 11)  Very Large Telescope
 * 12)  Large Binocular Telescope
 * 13)  Mount Wilson Observatory
 * 14)  Very Large Array
 * 15)  Very Long Baseline Array
 * 16)  Arecibo Observatory
 * 17)  Green Bank Telescope
 * 18)  Effelsberg 100-m Radio Telescope
 * 19)  Low-Frequency Array
 * 20)  MeerKAT
 * 21)  Square Kilometre Array
 * 22)  Extremely Large Telescope
 * 23)  Giant Magellan Telescope
 * 24)  Wise Observatory
 * 25)  South Pole Telescope
 * 26)  Jodrell Bank Observatory

=Space =

Basics

 * 1)  Spaceflight (Level 3)
 * 2)  Sub-orbital spaceflight
 * 3)  Orbital spaceflight
 * 4)  Spacecraft (Level 4)
 * 5)  Rocket (Level 3)
 * 6)  Launch pad (Level 4)
 * 7)  Launch vehicle (Level 4)
 * 8)  Rocket engine (Level 4)
 * 9)  Satellite (Level 3)
 * 10)  Space station (Level 3)
 * 11)  Astronaut (Level 4)
 * 12)  Space suit
 * 13)  Space capsule
 * 14)  Uncrewed spacecraft
 * 15)  Interstellar travel
 * 16)  Space colonization
 * 17)  Space settlement
 * 18)  Space industry

Programs and launch sites

 * 1)   NASA (Level 4)
 * 2)  Apollo program (Level 4)
 * 3)  Kennedy Space Center (Level 4)
 * 4)  Project Gemini
 * 5)  Project Mercury
 * 6)  Soviet space program (Level 4)
 * 7)  Baikonur Cosmodrome (Level 4)
 * 8)  Vostok programme
 * 9)  Voskhod programme
 * 10)  Soyuz programme
 * 11)  Roscosmos (Level 4)
 * 12)  European Space Agency (Level 4)
 * 13)  China National Space Administration (Level 4)
 * 14)  ISRO
 * 15)  Israel Space Agency
 * 16)  JAXA

Crewed vehicles

 * 1)  Apollo 11
 * 2)   International Space Station (Level 4)
 * 3)   Mir (Level 4)
 * 4)  Salyut 1
 * 5)  Space Shuttle (Level 4)
 * 6)  Space Shuttle Challenger disaster
 * 7)   Space Shuttle Columbia disaster
 * 8)   Saturn V (Level 4)
 * 9)  Soyuz (spacecraft) (Level 4)
 * 10)  Skylab
 * 11)  Tiangong space station
 * 12)  Vostok 1

Unmanned spacecraft

 * 1)  Sputnik 1 (Level 4)
 * 2)  Sputnik 2
 * 3)  Luna 2
 * 4)  Luna 3
 * 5)  Mariner 2
 * 6)  Luna 9
 * 7)  Voyager program (Level 4)
 * 8)  Voyager 1
 * 9)  Voyager 2
 * 10)  Voyager Golden Record
 * 11)  Pioneer program
 * 12)  Pioneer 10
 * 13)  Pioneer 11
 * 14)  New Horizons
 * 15)  Galileo project
 * 16)   Cassini–Huygens
 * 17)  Cosmic Background Explorer
 * 18)  Wilkinson Microwave Anisotropy Probe
 * 19)  MESSENGER

Rovers

 * 1)  Rover (space exploration)
 * 2)  Mars rover
 * 3)  Perseverance (rover)
 * 4)  Curiosity (rover)
 * 5)  Spirit (rover)
 * 6)  Opportunity (rover)
 * 7)  Sojourner (rover)
 * 8)  Lunar rover
 * 9)  Lunokhod 1

=Transportation =

Basics

 * 1)  Transport (Level 2)
 * 2)  Public transport (Level 4)
 * 3)  Private transport
 * 4)  Travel (Level 4)
 * 5)  Airbag
 * 6)  Passenger
 * 7)  Intermodal passenger transport
 * 8)  Freight transport (Level 4)
 * 9)  Cargo (Level 4)
 * 10)  Induced demand
 * 11)  Seat belt
 * 12)  Traffic
 * 13)  Traffic collision (Level 4)
 * 14)  Traffic congestion
 * 15)  Vehicle (Level 4)
 * 16)  Motor vehicle
 * 17)  Alternative fuel vehicle
 * 18)  Electric vehicle
 * 19)  Battery electric vehicle
 * 20)  Hybrid vehicle

Concepts of ground transport

 * 1)  Land transport
 * 2)   Road transport (Level 4)
 * 3)  Breakdown (vehicle)
 * 4)  Charging station
 * 5)  Driving (Level 4)
 * 6)   Filling station (Level 4)
 * 7)  Parking (Level 4)
 * 8)  Parking lot
 * 9)  Service (motor vehicle)
 * 10)  Automobile repair shop
 * 11)  Bus garage
 * 12)  Car wash
 * 13)  Rail yard
 * 14)  Rest area
 * 15)  Tire (Level 4)
 * 16)  Transport hub
 * 17)  Bus station
 * 18)  Bus stop
 * 19)  Train station (Level 4)
 * 20)  Goods station
 * 21)  Railway platform
 * 22)  Park and ride

Road infrastructure
For bridges and tunnels, see transport infrastructure in #Infrastructure section.
 * 1)  Road (Level 3)
 * 2)  Byway (road)
 * 3)  Dirt road
 * 4)  Highway (Level 4)
 * 5)  Controlled-access highway (Level 4)
 * 6)  Road junction
 * 7)  Interchange (road)
 * 8)  Stack interchange
 * 9)  Intersection (road)
 * 10)  Traffic light
 * 11)  Traffic sign
 * 12)  Toll road
 * 13)  Footpath
 * 14)  Pedestrian crossing
 * 15)  Pedestrian zone
 * 16)  Sidewalk
 * 17)  Trail (Level 4)
 * 18)  Cycling infrastructure
 * 19)  Bicycle boulevard
 * 20)  Bike lane
 * 21)  Bicycle parking rack
 * 22)  Shared-use path
 * 23)  Bicycle-sharing system
 * 24)  Cycle track

Motorized road transport

 * 1)   Auto rickshaw
 * 2)  Bus (Level 4)
 * 3)  Articulated bus
 * 4)  Bus rapid transit
 * 5)  Coach (bus)
 * 6)  Double-decker bus
 * 7)  Minibus
 * 8)  Public transport bus service
 * 9)  School bus
 * 10)  Trolleybus
 * 11)  Car (Level 3)
 * 12)  Convertible
 * 13)  Coupe
 * 14)  Electric car
 * 15)  Grand tourer
 * 16)  Hatchback
 * 17)  Limousine
 * 18)  Luxury car
 * 19)  Microcar
 * 20)  Muscle car
 * 21)  Sedan (automobile)
 * 22)  Sports car
 * 23)  Station wagon
 * 24)  Supercar
 * 25)  T-top
 * 26)  Motorcycle (Level 4)
 * 27)  Chopper (motorcycle)
 * 28)  Minibike
 * 29)  Moped
 * 30)  Rat bike
 * 31)  Scooter (motorcycle)
 * 32)  Kick scooter
 * 33)  Motorized scooter
 * 34)  Scooter-sharing system
 * 35)  Sport bike
 * 36)  Off-road vehicle
 * 37)  All-terrain vehicle
 * 38)  Dune buggy
 * 39)  Snowmobile
 * 40)  Shared transport
 * 41)  Carpool
 * 42)  Demand-responsive transport
 * 43)  Truck (Level 4)
 * 44)  Flatbed truck
 * 45)  Monster truck
 * 46)  Pickup truck
 * 47)  Semi-trailer truck
 * 48)  SUV
 * 49)  Van (Level 4)
 * 50)  Minivan
 * 51)  Vehicle for hire
 * 52)  Motorcycle taxi
 * 53)  Share taxi
 * 54)  Taxi (Level 4)

Rail and cable transport

 * 1)  Rail transport (Level 4)
 * 2)  Railway track (Level 4)
 * 3)  Elevated railway
 * 4)  Railway electrification
 * 5)   Train (Level 3)
 * 6)  Locomotive (Level 4)
 * 7)  Electric locomotive
 * 8)  Diesel locomotive
 * 9)  Steam locomotive (Level 4)
 * 10)  Railroad car
 * 11)  Rolling stock
 * 12)  Passenger train
 * 13)  Rail freight transport
 * 14)  Freight train
 * 15)  Cable transport (Level 4)
 * 16)  Aerial tramway (Level 4)
 * 17)  Cable car (railway)
 * 18)  Funicular
 * 19)  Gondola lift
 * 20)  Ski lift
 * 21)  High-speed rail (Level 4)
 * 22)  Tram (Level 4)
 * 23)  Interurban
 * 24)  Light rail
 * 25)   Rapid transit (Level 4)
 * 26)  Commuter rail
 * 27)  Medium-capacity rail system
 * 28)  Monorail (Level 4)

Animal-powered transport

 * 1)  Carriage (Level 4)
 * 2)  Cart (Level 4)
 * 3)  Horsecar
 * 4)  Saddle (Level 4)
 * 5)  Stirrup
 * 6)  Stagecoach

Human-powered transport

 * 1)   Bicycle (Level 3)
 * 2)  Bicycle brake
 * 3)  Bicycle gearing
 * 4)  Derailleur
 * 5)  Shifter (bicycle part)
 * 6)  BMX bike
 * 7)  Electric bicycle
 * 8)  Mountain bike
 * 9)  Penny-farthing
 * 10)  Recumbent bicycle
 * 11)  Tandem bicycle
 * 12)  Handcar
 * 13)  Rickshaw (Level 4)
 * 14)  Tricycle
 * 15)  Unicycle

Specific-purpose transportation
For medical transport, see Medical section
 * 1)  Baby transport (Level 4)
 * 2)  Fire engine
 * 3)  Paratransit
 * 4)  Pipeline (Level 4)
 * 5)  Police car
 * 6)  Heavy equipment
 * 7)  Bulldozer
 * 8)  Dump truck
 * 9)  Excavator
 * 10)  Road roller
 * 11)  Steamroller
 * 12)  Tractor (Level 4)

Specific automobiles

 * 1)  Ford Model T
 * 2)  Volkswagen Beetle

Naval transport
''For military watercraft, see Military technology. For pier and port, see coastal infrastructure.''


 * 1)  Maritime transport (Level 4)
 * 2)  Ship (Level 3)
 * 3)  Anchor
 * 4)  Watercraft
 * 5)  Buoy
 * 6)  Canal (Level 3)
 * 7)  Lock (water navigation) (Level 4)
 * 8)  Barge (Level 4)
 * 9)  Boat (Level 4)
 * 10)  Canoe (Level 4)
 * 11)  Cargo ship (Level 4)
 * 12)  Container ship
 * 13)  Ferry (Level 4)
 * 14)  Fishing vessel (Level 4)
 * 15)  Hospital ship
 * 16)  Hovercraft (Level 4)
 * 17)  Hydrofoil
 * 18)  Icebreaker
 * 19)  Kayak
 * 20)  Merchant ship (Level 4)
 * 21)  Motor ship
 * 22)  Motorboat
 * 23)  Multihull
 * 24)  Catamaran
 * 25)  Naval architecture
 * 26)  Outrigger (nautical)
 * 27)  Passenger ship (Level 4)
 * 28)  Cruise ship
 * 29)  Ocean liner
 * 30)  Personal watercraft
 * 31)  Riverboat (Level 4)
 * 32)  Sail (Level 4)
 * 33)  Sailboat
 * 34)  Schooner
 * 35)  Sloop
 * 36)  Sailing ship (Level 4)
 * 37)  Caravel
 * 38)  Clipper
 * 39)  Junk (ship)
 * 40)  Sailing (Level 4)
 * 41)  Scuba set
 * 42)  Snorkel (swimming)
 * 43)  Shipbuilding (Level 4)
 * 44)  Steamboat (Level 4)
 * 45)  Steamship
 * 46)  Paddle steamer
 * 47)  Submersible
 * 48)  Diving bell
 * 49)  Remotely operated underwater vehicle
 * 50)  Tanker (ship) (Level 4)
 * 51)  Oil tanker
 * 52)  Tugboat

Specific piers and ports

 * 1)  Port of Singapore
 * 2)  Port of Ningbo-Zhoushan
 * 3)  Port of Busan
 * 4)  Port of Rotterdam
 * 5)  Port of Jebel Ali
 * 6)  Port of Los Angeles
 * 7)  Port of New York and New Jersey
 * 8)  Port of Port Hedland
 * 9)  Port of Yokohama
 * 10)  Port of Kobe
 * 11)  Port of Hamburg
 * 12)  PortMiami
 * 13)  Port of Barcelona

Aviation

 * 1)  Aviation (Level 4)
 * 2)  Aircraft (Level 3)
 * 3)  Cargo aircraft
 * 4)  Jet aircraft (Level 4)
 * 5)  Line-replaceable unit
 * 6)  Unmanned aerial vehicle (Level 4)
 * 7)  Airport (Level 4)
 * 8)  Airport terminal
 * 9)  Helipad
 * 10)  Runway
 * 11)  Air traffic control (Level 4)
 * 12)  Parachute (Level 4)
 * 13)  Wingsuit flying
 * 14)  Aerostat
 * 15)  Balloon (aeronautics) (Level 4)
 * 16)   Hot air balloon (Level 4)
 * 17)  Gas balloon
 * 18)   Airship (Level 4)
 * 19)  Blimp
 * 20)  Rigid airship
 * 21)  Semi-rigid airship
 * 22)  Fixed-wing aircraft (Level 4)
 * 23)  Airplane (Level 4)
 * 24)  Glider (aircraft) (Level 4)
 * 25)  Ultralight aviation
 * 26)  Powered paragliding
 * 27)  Rotorcraft
 * 28)  Helicopter (Level 4)
 * 29)  Aircraft flight control system
 * 30)  Fly-by-wire
 * 31)  Aircraft engine (Level 4)
 * 32)  Auxiliary power unit
 * 33)   Jet engine (Level 4)
 * 34)  Turbofan
 * 35)  Turbojet
 * 36)  Radial engine
 * 37)  Turboprop
 * 38)  Turboshaft
 * 39)  Thrust reversal
 * 40)  Airframe
 * 41)  Aircraft fairing
 * 42)  Empennage
 * 43)  Fuselage
 * 44)  Landing gear
 * 45)  Wing (Level 4)
 * 46)  Airfoil
 * 47)  Wingtip device
 * 48)  Avionics
 * 49)  ACARS
 * 50)  Airborne collision avoidance system
 * 51)  ARINC 429
 * 52)  Autopilot
 * 53)  FADEC
 * 54)  Flight management system
 * 55)  Flight recorder
 * 56)  Future Air Navigation System
 * 57)  Health and usage monitoring systems
 * 58)  Integrated modular avionics
 * 59)  Cockpit
 * 60)  Flight instruments
 * 61)  Glass cockpit
 * 62)  Flight control surfaces
 * 63)  Aileron
 * 64)  Air brake (aeronautics)
 * 65)  Elevator (aeronautics)
 * 66)  Flap (aeronautics)
 * 67)  Leading-edge slat
 * 68)  Spoiler (aeronautics)
 * 69)  Stabilizer (aeronautics)
 * 70)  Trim tab

Specific aircraft
For military aircraft, see Military technology


 * 1)  Airbus A300
 * 2)  Airbus A320 family
 * 3)  Airbus A330
 * 4)  Airbus A350
 * 5)  Airbus A380
 * 6)  Antonov An-225 Mriya
 * 7)  Boeing 707
 * 8)  Boeing 727
 * 9)  Boeing 737
 * 10)  Boeing 747
 * 11)  Boeing 757
 * 12)  Boeing 767
 * 13)  Boeing 777
 * 14)   Boeing 787 Dreamliner
 * 15)  De Havilland Canada Dash 8
 * 16)  Cessna 172
 * 17)  Concorde
 * 18)  de Havilland Comet
 * 19)  Douglas DC-3
 * 20)  Douglas DC-6
 * 21)  Douglas DC-8
 * 22)  Embraer E-Jet family
 * 23)  Ilyushin Il-76
 * 24)  Lockheed Constellation
 * 25)  McDonnell Douglas DC-9
 * 26)  McDonnell Douglas DC-10
 * 27)  Mil Mi-8
 * 28)  Tupolev Tu-154
 * 29)  Wright Flyer

Asia

 * 1)  Beijing Capital International Airport
 * 2)  Dubai International Airport
 * 3)  Haneda Airport
 * 4)  Hong Kong International Airport
 * 5)  Indira Gandhi International Airport
 * 6)  Shanghai Pudong International Airport

Europe

 * 1)  Charles de Gaulle Airport
 * 2)  Heathrow Airport
 * 3)  Sheremetyevo International Airport

North America

 * 1)  Hartsfield–Jackson Atlanta International Airport
 * 2)  John F. Kennedy International Airport
 * 3)  Los Angeles International Airport
 * 4)  O'Hare International Airport

Ground transportation networks
See Geography/Physical for Maritime transportation network. See Society/Politic and economic for companies that operate transportation networks.
 * 1)  Intercontinental and transoceanic fixed links
 * 2)  Arab Mashreq International Road Network
 * 3)  Asian Highway Network
 * 4)  Autobahn
 * 5)  Camino de Santiago
 * 6)  Interstate Highway System
 * 7)   U.S. Route 66
 * 8)  Roman roads
 * 9)  Appian Way
 * 10)  Trans-African Highway network
 * 11)  Trans-European Transport Network
 * 12)  Trans-European high-speed rail network
 * 13)  EuroVelo
 * 14)  European long-distance paths
 * 15)  Transcontinental railroad

Africa

 * 1)  Cairo Metro

Americas

 * 1)  Caracas Metro
 * 2)  Mexico City Metro
 * 3)  Santiago Metro
 * 4)  TransMilenio

Brazil

 * 1)  Rio de Janeiro Metro
 * 2)  São Paulo Metro

Canada

 * 1)   Montreal Metro
 * 2)  Toronto subway
 * 3)   SkyTrain (Vancouver)

United States

 * 1)   Bay Area Rapid Transit
 * 2)  Chicago "L"
 * 3)  Massachusetts Bay Transportation Authority
 * 4)  New York City Subway (Level 4)
 * 5)  Washington Metro

Asia

 * 1)  Dubai Metro
 * 2)  Transjakarta
 * 3)   Mass Rapid Transit (Singapore)
 * 4)  Taipei Metro
 * 5)  Tehran Metro

China

 * 1)  Beijing Subway
 * 2)  Chongqing Rail Transit
 * 3)  Guangzhou Metro
 * 4)   MTR
 * 5)  Shanghai Metro
 * 6)  Shenzhen Metro

India

 * 1)  Delhi Metro
 * 2)  Hyderabad Metro
 * 3)  Kolkata Metro
 * 4)  Mumbai Metro
 * 5)  Namma Metro

Japan

 * 1)  Hiroshima Electric Railway
 * 2)  Nagoya Municipal Subway
 * 3)  Osaka Metro
 * 4)  Sapporo Municipal Subway
 * 5)  Tokyo Metropolitan Bureau of Transportation
 * 6)  Tokyo Metro

South Korea

 * 1)  Busan Metro
 * 2)  Seoul Metropolitan Subway

Europe

 * 1)  Athens Metro
 * 2)  Brussels Metro
 * 3)  Budapest Metro
 * 4)  Istanbul Metro
 * 5)  Kyiv Metro
 * 6)  Prague Metro
 * 7)  Vienna U-Bahn

France

 * 1)  Lyon Metro
 * 2)  Paris Métro
 * 3)   Réseau Express Régional

Germany

 * 1)  Berlin U-Bahn
 * 2)  Munich U-Bahn
 * 3)  S-Bahn

Italy

 * 1)  Milan Metro
 * 2)  Rome Metro

Netherlands

 * 1)  Amsterdam Metro
 * 2)  Rotterdam Metro

Russia

 * 1)  Moscow Metro
 * 2)  Saint Petersburg Metro

Scandinavia

 * 1)   Copenhagen Metro
 * 2)  Helsinki Metro
 * 3)  Oslo Metro
 * 4)  Stockholm Metro

Spain

 * 1)  Barcelona Metro
 * 2)  Madrid Metro

United Kingdom

 * 1)   London Underground (Level 4)

High-speed rail

 * 1)  Acela
 * 2)  AVE
 * 3)  China Railway High-speed
 * 4)   Eurostar
 * 5)  Frecciarossa
 * 6)   Intercity Express
 * 7)  Korea Train Express
 * 8)  Shinkansen (Level 4)
 * 9)  Taiwan High Speed Rail
 * 10)   TGV
 * 11)  Sapsan

Railway lines

 * 1)  Trans-Australian Railway
 * 2)  Chinese Eastern Railway
 * 3)  Trans-Mongolian Railway
 * 4)   Trans-Siberian Railway (Level 4)

Railway services

 * 1)  Indian Pacific
 * 2)  Orient Express