AngularJS is a JavaScript framework that extends HTML with new attributes, making it easier to create single-page applications (SPAs). It is a popular choice for developing web applications because it is:

• Declarative: AngularJS code is declarative, which means that you can express what you want your application to do, rather than how to do it. This makes AngularJS code easier to read and understand.
• Data-driven: AngularJS applications are data-driven, which means that the UI of your application is automatically updated when the data changes. This makes your application more responsive and interactive.
• Testable: AngularJS applications are easy to test, because the framework provides a number of tools and techniques for testing your code.
• Extensible: AngularJS is extensible, which means that you can customize it to meet your specific needs. You can add new features, or modify existing features, to create a framework that is tailored to your application.

AngularJS is a powerful and versatile framework that can be used to create a wide variety of web applications. It is a good choice for developers who want to create high-quality, responsive, and data-driven applications.

Here are some of the main features of AngularJS:

• Directives: Directives are custom HTML attributes that extend the functionality of HTML. They can be used to do things like bind data to HTML elements, create reusable components, and handle user input.
• Expressions: Expressions are snippets of JavaScript code that can be used to dynamically update the content of HTML elements. They can be used to bind data to HTML elements, calculate values, and make decisions.
• Controllers: Controllers are JavaScript objects that control the behavior of an AngularJS application. They are responsible for handling user input, updating the application's data, and rendering the application's UI.
• Modules: Modules are a way of organizing AngularJS code. They can be used to group related code together, and to make it easier to reuse code across multiple applications.

AngularJS is a mature and well-supported framework. It has a large and active community of developers, and there are a number of resources available to help you learn and use AngularJS. If you are looking for a powerful and versatile JavaScript framework for developing web applications, AngularJS is a good choice.