Before we get started with building our application and integrating Facebook and all, let's first take a moment to learn about directives as we plan to integrate our Facebook authentication module as a directive.
A directive is a marker on a DOM element that tells AngularJS to transform the DOM element or attach a specified behavior to it. The marker would be a CSS class, a custom attribute, or a custom element name.
AngularJS comes with a large set of predefined directives, many of which we've already been using till now. Some of the built-in directives that we've used so far are ng-app
, ng-repeat
, ng-model
, and ng-view
.
One of the coolest features of AngularJS is the ability to create your own custom directives that can be created once and used multiple times within your application.