What is "angularjs-directives"
At a high level, directives are markers in a DOM element (such as an attribute, element name, comment, or CSS class) that inform the Angularjs HTML compiler ($ Compile) to attach specified behavior to that DOM element (for example, event listeners) or even to transform the GIFT element and its children.
Angularjs comes with a set of these built-in directives such as ngBind, ngModel and ngClass. Just as you create controllers and services, you can create your own directives to use Angularjs. When Angularjs initializes its application, the HTML compiler traverses the DOM correspondence directives regarding the DOM elements.