In this tutorial, we are going to discuss Bootstrapping in Angular application and also discuss the ng-app directive. When the document is loaded the ng-app directive will bind the Angular js functions with an application. Ng-app is the simplest attribute in angular, it has no value. Bootstrapping is done by the ng-app directive. Ng-app is most important directive in angular which informs that the document has the angular controls.
When you put ng-app inside HTML, it will tell angularjs to control the entire application of HTML. It can also be added in other element of the HTML like body. It is important to add in the parent element so that the child element can run the directives of the angular.
The double curly brackets syntax shows that the it has used one-way data binding or expression. If it is related with the variable it will keep the UI updated with the changes in value. If it is related to the expression, it will keep the UI update when the expression changes.
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