User:Faz Waris

Chapter 1

Introduction to Computer System

The word “Computer” is derived from the Latin word “Compute”, which means to Calculate. A computer is a programmable electronic device that can accept data, processes the given data by performing arithmetic (+,-, x, /) & logical (<,>,=,≠) operations on the data to produce the desired results.

Basic Terms in the Field of Computers When we talk about computers, it involves the following basic terms generally: i.	Hardware: A computer's hardware consists of electronic devices (every component ); the physical or tangible parts of the computer called hardware. Like Cables, Monitor, Keyboard, CPU, Mouse, Mother Board, RAM etc. ii. Software: A program or set of programs, used to give commands to the computer for the desired results. iii. Data:	A collection of raw facts and figures is called data, which can include text, numbers, images, audios and videos etc. iv. Information: The processed form of data is called information. It is an organized but more meaningful form of data. v.	User: A person who uses the computer system and its resources.

Information Processing Cycle (IPC) Information processing cycle consists of a series of tasks or steps required to convert data into information.

Characteristics of Computers Computers are powerful due to variety of reasons. They operate with amazing speed, accuracy, huge storage, reliability, consistency, diligence (A computer is free from monotony, tiredness, and lack concentration, No IQ and No Feelings). Types of Computers: There are three types of computers with respect to Operational Principle: 1.	Analogue Computers 2.	Digital Computers and 3.	Hybrid Computers Classification of Digital Computers (By Size & speed) Computers are mainly classified into four categories based on their processing speed, size, storage capacity etc. These are: 1.	Micro computer 2.	Mini computers 3.	Mainframe computers and 4.	Super computers. 1.	MICRO COMPUTERS Micro computers are commonly known as personal computers. These are small computers that are found in offices, schools, homes etc. (Figure1.1) These computers are designed to be used by one person at a time. They have Microprocessor chip as the CPU. Many models of Microcomputers are there – some sit on desktops, some stands on floors and some are portable. 1975, Ed Roberts, the "father of the microcomputer" designed the first microcomputer, the Altair 8800, which was produced by Micro Instrumentation and Telemetry Systems (MITS). The original IBM Personal Computer (PC) is shown in the picture. 2.	MINI (Midrange ) COMPUTERS Mini computers have more processing speed and larger storage capacity than Microcomputers. They are used in multi-user environments where more than one person is working on the computer at the same time. Mini computers were introduced in 1960s. The DEC PDP-12 minicomputer of 1969 is shown in the picture. 3.	MAINFRAME COMPUTERS Mainframe computers are more powerful than Mini computers. They are large and expensive computers that can handle a large number of users at the same time. It was introduced in 1970s. Nearly all mainframes (Figure 1.2) have the ability to run (or host) multiple operating systems. They are capable of storing large amount of instructions and information. They are best suited for big organizations, where centralized data storage and processing are required. The IBM 7094 Mainframe computer of 1970s is shown in the picture. 4.	SUPER COMPUTERS Super computers are the most powerful and expensive computers. They are built to process complex scientific calculations. They are mainly used in weather forecasting, nuclear research, launching of rockets, monitoring of satellites etc. The speed of a supercomputer is generally measured in "FLOPS" (FLoating point Operations Per Second). Created by	Installed at	Memory	Speed	Storage	Cost	RANK Cray Inc	Oak Ridge National Laboratory	710 TB	17.59 PFLOPS	10 PB	US$ 97 Million	TOP500: #1, Nov 12, 2012

Created by	Installed at	Memory	Speed	Storage	Cost	RANK NUDT	NUDT China 1375 TB	33.86 PFLOPS	12.4 PB	US$ 390 Million	TOP500: #1, June 2013 Super Computer of Pakistan NUST's new 132 Teraflop supercomputer has catapulted the Pakistani university's supercomputing center to the elite Top 200 list of supercomputing sites in the world, a list dominated by a handful of industrialized nations. National University of Science & Technology's supercomputer is named ScREC after its supercomputing research and education center. Created By: NUST Installed At: Research Centre for Modeling and Simulation (RCMS), NUST Speed: 132 TFLOPS Storage: 21.6 TB

Input and Input Devices Everything that we give to the computer system through input devices is called input. “An input device is any hardware component that allows you to enter data or instruction into a computer.” Sr#	Name	Sr#	Name 1	KEYBOARD 2

Track Ball

3	 MOUSE	4

GLIDE PAD

5

SCANNER 6

MICROPHONE 7

DIGITAL CAMERA 8	WEB CAM

9

BARCODE READER	10 JOY STICK 11	 LIGHT SENSOR	12 Optical Megnetic reader 13	 MEGNETIC INK CHARACTER READER	14 MEGNETIC INK CARD READER 15	 LIGHT PEN	16 FINGER PRINT READER

Biometric Input Devices: Output and Output Devices Everything that computer displays after processing is called output, which can be in hard / soft form. Computer hardware components that are used to receive processed information from computer are called output devices.

Sr#	Name	Picture

1	CRT (Cathode Ray Tube) Monitors and LCD (Liquid Crystal Display) Flat-Panel Displays LEDs, TFTs

2	Speakers

3	Printers (Impact Printers Dot Matrix Printer (Non-Impact Printers Ink jet Printer

4	Plotters

5	Projector / Multimedia

Memory and Processing The Microprocessor is key processing unit also called the central processing unit (CPU), interprets and carries out all the basic instructions that operate the computer.

Processor contains a Control Unit (CU) and an Arithmetic and Logic Unit (ALU). These two components work together to perform processing of operations. For every instruction, a processor repeats a set of four basic operations that makes the machine cycle. (Figure 1.3) •	Fetch: get data from Main Memory. •	Decode: Convert Data to Machine Understandable Language. •	Execute: Perform calculation on data, •	Store: Store the results in main memory. Primary memory, presently known as main memory or simply RAM (Random Access Memory), is the only one directly accessible to the CPU. RAM varies in size like 128 MB, 256 MB, 512 MB to 2 GB. RAM cannot store data and instruction permanently. When we switch off the computer, all data and instructions from RAM are washed or vanished. Therefore it is called volatile memory.

ROM stands for Read only Memory. It consists of those instructions that prepare the computer for use. These instructions can only be read but cannot be changed or deleted. When we switch off the computer, the instructions stored in the ROM are not lost. Therefore it is called a non-volatile memory.

Digital Data Storage: Storage is the area where data can be kept(left) on a permanent basis, when it is not immediately needed for processing. A digital data storage system has two main components: Storage Medium: A storage medium (media is the plural) is the disk, tape, CD, DVD, paper, or other substance that contains data. Storage Devices: A storage device is the mechanical apparatus that records and retrieves data from a storage medium, like hard disk drives, CD drives, DVD drives, Blu-ray drives, and flash drives. Storage devices also known as Secondary (Auxiliary) Storage Devices (SSD,ASD) Storage media hold data, even when the computer is turned off. So that all Secondary storage devices are nonvolatile. Storage Capacity 1 Byte	23 or 8 bits 1 Kilo Byte (KB)	210 or 1024 Bytes 1 Million (Mega) Byte (MB)	220 or 1024 Kilo Bytes 1 Billion (Giga) Bytes (GB)	230 or 1024 Mega Bytes 1 Trillion (Tera) Bytes (TB)	240 or 1024 Giga Bytes 1 Quadrillion (Peta) Bytes (PB)	250 or 1024 Tera Bytes 1 Exabyte’s (EB)	260 or 1024 Peta Bytes 1 Billion Tera (Zetta) bytes (ZB)	270 or 1024 Exa Bytes 1 Septillion (Yotta) bytes (YB)	280 or 1024 Zetta Bytes Motherboard The mother board sometime called a system board is the main circuit board of the system unit. It is used to connect all kinds of hardware devices. (Figure No. 1.4) Ports: A 'port' serves as an interface between the computer and other components or peripheral devices. Physically, a port is a specialized outlet on a piece of equipment to which a plug or cable connects. (Figure No. 1.5) Computer Software Software, also called Programs. Software is a set of instructions that tells the computer what to do and how to do it. Basically there are two types of the Software. (i)	System Software: a.	Operating System b.	Drivers & Utility Software c.	Embedded Software (ii)	Application Software: a.	Word Processors (notepad, WordPad, Ms Word) b.	Entertainment Software (VLC, Windows Media Player) c.	Spreadsheet software (lotus123, Excel) d.	Database Software (Ms Access, SQL Server) e.	Presentational Software (PowerPoint, Flash) f.	Graphics (Ms paint, Corel, Photoshop) Keyboard A standard key board has almost 101/102 keys. There are two types of layouts of keyboard available, QWERTY, & non QWERTY Most keyboards use the QWERTY layout, named for the first six keys in the top row of letters.

Symbols of Keyboards Symbol	Name	Symbol	Name `	Grave Accent	~	Tilde !	Exclamation Sign	@	Commercial AT %	Percent Sign	^	Circumflex Sign or Caret &	Ampersand Sign orConcatenation Sign	+	Plus Sign or Sign of Addition (	Left or opening Parenthesis	)	Right or closing Parenthesis -	Hyphen	_	Underscore or Low Line =	Equals Sign	*	Asterisk [	Left Squares bracket	]	Right Square Brackets {	Left Curly Bracket	}	Right Curly Bracket ‘	Single Quotation Mark, or Apostrophe	“	Double Quotation Mark \	Reverse Slash, Or Reverse Solidus	¦	Vertical Bar or Broken bar or Pipe sign ,	Comma	<	Less-Than Sign .	Full Stop	>	Greater Than Sign /	Forward Slash, or Forward Solidus	? Question Mark Miscellaneous: 1.	Data has 7 types, which are, Alphabetic, Numeric, Alphanumeric, Sound, Images, Video, and pointing. 2.	Macro computers are also known as Main Frame Computers. 3.	LSI stands for Large Scale Integration. 4.	OCR Stand for Optical Character Recognition. 5.	OMR stand for Optical Mark Recognition. 6.	CBT stands for Computer Based Training. 7.	CAL stands for Computer Aided Learning. 8.	CAD stands for Computer Aided Design. 9.	4096 Bytes equal to 32768 bits 10.	PDA stands for Personal Digital Assistant. 11.	CMOS stands for Complementary Metal Oxide Semiconductor. 12.	BIOS stands for Basic Input Output System. 13.	The symbols are called Parenthesis. 14.	A standard 3.5” floppy Diskette can store data of 1.44MB. 15.	The first Pakistani designed super computer named ScREC built on September, 2012 at NUST. 16.	ISA stands for Industry Standard Architecture. 17.	IDE Stands for Integrated Drive Electronics 18.	CLI Stands for Command Line Interface 19.	PCI Stands for Peripheral Component Interconnect 20.	AGP Stands for Accelerated Graphic Port 21.	SCSI Stands for Small Computer System Interface 22.	SATA Stands for Serial Advanced Technology Attachment 23.	VGA Stands for Video Graphics Array 24.	DIMM Stands for Double Inline Memory Module. 25.	SIMM Stands for Single Inline Memory Module. 26.	RIMM Stands for Rambus In-line Memory Module. 27.	SDRAM Stands for Synchronous dynamic random-access memory 28.	DDR SDRAM Stands for Double data rate synchronous dynamic random-access memory 29.	IBM Stands for International Business Machine 30.	EIDE Stands for Enhanced Integrated Drive Electronics 31.	USB Stands for Universal Serial Bus. 32.	IEEE Stands for Institute of Electrical and Electronics Engineers 33.	ISO Stands for International Organization for Standardization 34.	EEPROM stands for Electrically Erasable Programmable Read only Memory 35.	A bus line, or bus width, or simply bus is an electronic pathway through which bits are transmitted within the CPU and between the CPU and other devices in the system unit. 36.	EDSAC stands for Electronic Delay Storage Automatic Calculator. 37.	EBCDIC stands for Extended Binary Coded Decimal Interchange Code 38.	An Inkjet printer is an example of Non impact Printer. 39.	ATM stands for Automatic Teller machine. 40.	The control unit stores the CPU's microcode, which contains the instructions for all the tasks the CPU can perform. 41.	The control unit directs the flow of data through the CPU, and to and from other devices. 42.	FPD is abbreviation of Flat Panel Displays. 43.	FAX is short form of facsimile. 44.	ASCII stands for American Standard Code for Information Interchange. 45.	LED stands for Light Emitting Diode. 46.	LASER Stands for Light Amplification through Stimulated Emission of Radiation. 47.	UNIVAC Stands for Universal Automatic Computer. 48.	VDT stands for Video/Visual Display Terminal. 49.	VLSI stands for Very Large Scale Integration. 50.	Defragmenter is the example of system software. 51.	Database software belongs to application software.
 * 1) 	Hash or Number Sign	$	Dollar Sign
 * Sami Colon	:	Colon

Exercise Q1. Fill in the Blanks 1.	The Word computer is derived from the _________________ word “COMPUTE”, which means “TO CALCULATE”. 2.	The processed form of data is called _________________. 3.	The physical or tangible parts of the computer called _____________. 4.	A command is used to tell the computer, _____________ and how to do. 5.	Raw facts and figures are called data which is plural form of _____________. 6.	_____________computers introduced in 1960. 7.	IPC consists of a series of tasks required to _____________ into information. 8.	_____________computers are also known as Personal Computers (PC). 9.	LCD Stands for ____________________. 10.	CRT stands for ____________________. 11.	Plotter is an __________ device. 12.	Anything that we feed to the computer is called __________. 13.	The devices that are used to enter data into the computers are called __________ devices. 14.	Printers are output type of devices, which produce output in the form of __________. 15.	Ed. Roberts famous as Father of _____________________. 16.	A ____________ Keyboard has 101/102 no. of keys. 17.	CPU has two parts, ____________ and ________________________. 18.	CPU stands for ____________________________ 19.	Machine cycle is a series of steps, each of which named as ________, ________, ________, and ________. 20.	CU stands for ________________________. 21.	ROM is a ________________________ memory. 22.	RAM Stands for ________________________. 23.	RAM is also known as ________ Memory. 24.	The term _____ refers to the amount of memory required to store one Binary Digit (either 0 or 1). 25.	IPC stands for __________________________________ 26.	Numeric pad activates from ___________ key. 27.	Modifier Keys are _____, ______, and ________ Keys. 28.	The 1st Microcomputer Altair 8800 designed by ________. 29.	MITS stands for ____________________________________________. 30.	Because RAM is a _____ memory, it needs a constant supply of power to keep data. 31.	The term BYTE refers to the amount of memory required to store __________. 32.	Mega Byte unit of storage is used to represent __________ bytes of data. 33.	256 bits = ____ bytes. 34.	Giga Byte unit of storage is used to represent ______________ bytes of data. 35.	Microphone is used to record ________ in the computer. 36.	PFLOPS Stands for ___________________________________________. 37.	DVD Stands for ___________________________________________. 38.	A barcode reader (or barcode scanner) is an electronic device for reading printed __________. 39.	Scanner is used to enter __________ type of data into the computer. 40.	Hard disk consists of more than one metal plates coated with __________ Material. 41.	___________________ is famous as father of modern age computers. 42.	Numeric keypad’s 1, 2, 3, 4, 6, 7, 8, 9, keys used as _____________ keys, when num lock key is turned off. 43.	TFT stands for ____________________ 44.	An operating system is _________ software.

Q2. True/False 1.	Information is output of computer. 2.	Multimedia is a combination of text, graphics, audio and video. 3.	Arrow keys, Page Up, and Page down Keys belong to Navigation Keys. 4.	1024 trillion bytes are equal to 1048576 billion Bytes. 5.	A byte is equal to 23 bits. 6.	Gigahertz (GHz) = 1million cycle per second. 7.	CRT is physical Mechanism used for the Printers. 8.	Gigahertz (GHz) = I024 million cycle per second. 9.	Storage means to keep something for later use. 10.	VDU stands for Visual Display Unit 11.	A byte is the basic unit of storage. 12.	Operating system is Loaded into ROM, when computer starts. 13.	CRT is physical Mechanism used in Monitors. 14.	RAM is much faster than Cache memory. 15.	Operating system is example of system software 16.	Processors contain high speed storage locations called registers. 17.	Non Volatile does not lose its contents even power is switched off. 18.	Each byte reside in the memory, its location identifier is called memory address. 19.	Decode means converting data from human to machine understandable language. 20.	There are three types of computers according to their working principal. 21.	The port, in which Keyboard plugged, is called PS/2 port. 22.	Hard-disk uses Magnetic Oxide method to store data on disk surface. 23.	Floppy drive made of plastic named Mylar. 24.	Windows VISTA is developed by Sun Solaris. 25.	Windows 3.1 is the 1st GUI Operating System. 26.	Hot processors make mistakes or even melt important part on the chip. 27.	Abacus is first computer 28.	The process of performing all operations of a computer is called Processing. 29.	ASCII is abbreviating of American Standard Code for Information Interchange. 30.	Audio output device can output only music.

Practical 1: Demonstrate Basic Computer components, how to Start a Computer and Booting Process? Practical 2: Introduction and Identification of Motherboard Components? Practical 3: Identify & Label the Different hardware components of system and show the sheet to your Instructor. (Figure No. 1.6) Practical 4: Label and Identify the Different Ports and Connectors of the System Unit and show the sheet to your Instructor. (Figure No. 1.7) Practical 5: Label and Identify the Different Keys of Keyboard and show the sheet to your Instructor. (Figure No. 1.8) Practical 6: Plug & unplug of different input devices to computer. Practical 7: Plugging different storage devices like Hard Disk, Flash, & CD. Practical 8: Plug and unplug of different output devices. Assignment: 1Give the Names of different Primary Storage and Secondary Storage Devices Separately and show the sheet to your Instructor. Assignment: 2Give the Names of different Sequential Access and Random Access Storage Devices Separately and show the sheet to your Instructor. Assignment: 3Arrange the Following Storage Devices according to their Speed. Hard Drive, Ram, Cache Memory, Registers, Magnetic Tape