Angular (web framework)

Angular (also referred to as "Angular 2+") is a TypeScript-based free and open-source single-page web application framework. It is developed by Google and by a community of individuals and corporations. Angular is a complete rewrite from the same team that built AngularJS. The Angular ecosystem consists of a diverse group of over 1.7 million developers, library authors, and content creators. According to the Stack Overflow Developer Survey, Angular is one of the most commonly used web frameworks, similar to React.

Differences between Angular and AngularJS
Google designed Angular as a ground-up rewrite of AngularJS. Unlike AngularJS, Angular does not have a concept of "scope" or controllers; instead, it uses a hierarchy of components as its primary architectural characteristic. Angular has a different expression syntax, focusing on  for property binding, and   for event binding. Angular recommends the use of Microsoft's TypeScript language, which introduces features such as static typing, generics, and type annotations.

Component-Based Architecture
Angular uses a component-based architecture, which allows developers to build encapsulated, reusable user interface elements. Each component encapsulates its own HTML, CSS, and TypeScript, making it easier to manage and test individual pieces of an application.

Data Binding
Angular supports two-way data binding, which synchronizes data between the model and the view. This ensures that any changes in the view are automatically reflected in the model and vice versa.

Dependency Injection
Angular has a built-in dependency injection system that makes it easier to manage and inject dependencies into components and services. This promotes modularity and easier testing.

Directives
Angular extends HTML with additional attributes called directives. Directives offer functionality to change the behavior or appearance of DOM elements.

Routing
Angular includes a router that allows developers to define and manage application states and navigation paths, making it easier to build single-page applications with complex routing.

Angular CLI
The Angular CLI (Command Line Interface) provides a set of tools for creating, building, testing, and deploying Angular applications. It enables rapid application setup and simplifies ongoing development tasks.

Server-Side Rendering
Angular has the official support for Server-Side Rendering. This functionality improves the application's load time and performance. Server-side rendering also enhances search engine optimization by making content more accessible to web crawlers.

History
Angular 2.0 was announced at the ng-Europe conference 22–23 October 2014. On April 30, 2015, the Angular developers announced that Angular 2 moved from Alpha to Developer Preview. Angular 2 moved to Beta in December 2015, and the first release candidate was published in May 2016. The final version was released on 14 September 2016.

Version 8 of Angular introduced a new compilation and rendering pipeline, Ivy, and version 9 of Angular enabled Ivy by default. Angular 13 removed the deprecated former compiler, View Engine.

Naming
The rewrite of AngularJS was called "Angular 2", but this led to confusion among developers. To clarify, the team announced that separate names should be used for each framework with "AngularJS" referring to the 1.X versions and "Angular" without the "JS" referring to versions 2 and up.

Future releases
Since v9, the Angular team has moved all new applications to use the Ivy compiler and runtime. They will be working on Ivy to improve output bundle sizes and development speeds.

Each version is expected to be backward-compatible with the prior release. The Angular development team has pledged to do twice-a-year upgrades.

Support policy and schedule
All the major releases are supported for 18 months. This consists of 6 months of active support, during which regularly-scheduled updates and patches are released. It is then followed by 12 months of long-term support (LTS), during which only critical fixes and security patches are released. Angular versions v2 to v15 are no longer under support.

Angular Material
Angular Material is a UI component library that implements Material Design in Angular. It provides a collection of reusable components that adhere to Google's Material Design specifications, aiming to offer a consistent user interface across different devices and platforms.

Angular Material includes a variety of UI components such as buttons, cards, dialogs, grids, and form controls. These components are designed to be customizable and easy to integrate into Angular applications. Additional features of Angular Material include support for responsive design, theming, and accessibility.

Angular Elements
In 2018, Angular 6 introduced Angular Elements, enabling developers to package Angular components as custom web elements, which are part of the web components set of web platform APIs.