What is the difference between AngularJS and Angular 2?

AngularJS and Angular 2 (and later versions of Angular) are two different frameworks for building web applications, with significant differences in terms of architecture, syntax, and features.

AngularJS is an older version of the framework that was initially released in 2010. It uses a two-way data binding approach, which means that changes in the model or view are automatically reflected in the other. It also relies on controllers and $scope to manage application data and logic. AngularJS is built on top of JavaScript and uses HTML as a templating language.

Angular 2, on the other hand, is a complete rewrite of AngularJS and was released in 2016. It uses a one-way data binding approach, which means that changes in the model are not automatically reflected in the view. Instead, it uses a hierarchical component-based architecture, where components encapsulate application data and behavior. It is built on top of TypeScript, a superset of JavaScript that includes additional features such as static typing and object-oriented programming constructs.

Some other differences between AngularJS and Angular 2 include:

• Syntax: AngularJS uses directives and filters to manipulate HTML, while Angular 2 uses components and pipes.
• Modules: Angular 2 introduced a module system for managing dependencies and organizing code, which was not present in AngularJS.
• Performance: Angular 2 offers improved performance and faster rendering than AngularJS, thanks to its use of a virtual DOM and other optimizations.

Overall, while AngularJS and Angular 2 share some similarities, they are fundamentally different frameworks with different approaches to building web applications.