AngularJS ng-app directive
ng-app directive define the start point of the any angular application. It specifies the root element of the application. any AngularJS application must define the root element using ng-app to auto-bootstrap as an application.
<div ng-app="myCalculation" ng-controller="CalculationController">
<p>Addition
of number: {{a}} + {{b}} = {{ a+b }}</p>
<p>Substraction
of number: {{a}} - {{b}} = {{ a-b }}</p>
<p>Multiplication
of number: {{a}} * {{b}} = {{ a*b }}</p>
<p>Division
of number: {{a}} / {{b}} = {{ a/b }}</p>
</div>
<script>
var
myapp = angular.module('myCalculation', []);
myapp.controller('CalculationController',
function ($scope) {
$scope.a = 20;
$scope.b = 4
});
</script>
Output:-
