Controllers in AngularJs
Controllers in AngularJs are not, strictly speaking, controllers. In fact AngularJs does not call itself an MVC framework, it calls itself an MVW (model-view-whatever) framework instead. That being said, that si relevant to academic purist's point of view. Through a practical lens, AngularJs controllers are controllers.
Syntax:
angular.module('application', []).controller('FooCtrl', function($scope) {
$scope.someProperty = 'More exclamation marks';
$scope.someAction = function() {
$scope.someProperty += '!';
};
});
The $scope object is prototypically inherited from its parent's
$scope object - in this case the main application object.
It is made available through AngularJs' dependency injection framework.
This in itself is a fascinating topic that warrants a discussion of its own,
as it is a beautiful piece of software engineering and architecture.
Understanding it lies at core of understanding AngularJs.
Unfortunately, this is not one of the criteria for comparison. I would however, suggest this article on understanding dependency injection for a primer on the basics; and this article on inheritance patterns as further reading.