To use AngularJS, first download the AngularJS library from AngularJS offical website AngularJS.org -> Download -> Angular.min.js
or
You can also use Google CDN (Content Delivery Network)

Syntax:
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.6.4/angular.min.js"></script>

The basic topic of AngularJS are directives, expressions, filters, modules, and controllers.

AngularJS extends HTML attributes with Directives, and binds data to HTML with Expressions.

AngularJS expressions can be written inside double braces: {{ expression }}.

Or

AngularJS expressions can also be written inside a directive: ng-bind="expression".