Summary

AngularJS directives extend the behavior of HTML. You can apply directives to AngularJS templates as HTML elements, attributes, and classes. You define the functionality of directives by using JavaScript code. AngularJS provides several built-in directives that interact with form elements, bind data in the scope to the view, and interact with browser events. For example, ngModel binds the value of a form element directly to the scope. When the scope value changes, so does the value displayed by the element and vice versa.

One of the most powerful features of AngularJS is the ability to create your own custom directives. Implementing a custom directive in code is simple using the directive() method on a Module object. However, directives can also be very complex because of the myriad of ways they can be implemented.