Hi rani,
The ng-init directive evaluates the given expression(s) in the current scope.
The ng-init directive can add some unnecessary logic into the scope, and you are recommended to do your evaluations in a controller instead.
There are only a few appropriate uses of ngInit:
Aliasing special properties of ngRepeat.
Initializing data during development.
Injecting data via server side scripting.
For more details refer below link.
https://www.w3schools.com/angular/ng_ng-init.asp
https://docs.angularjs.org/api/ng/directive/ngInit
Syntax
<element ng-init="expression" ></element>
Example
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>ng-init directive example</title>
</head>
<body>
<script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/angular.js/1.7.8/angular.min.js"></script>
<script type="text/javascript">
var app = angular.module('MyApp', []);
</script>
<div ng-app="MyApp" ng-init="Number1=50;Number2=25">
<p>Number 1 is <b>{{Number1}}.</b></p>
<p>Number 2 is <b>{{Number2}}.</b></p>
Sum of Number 1 and Number 2 is <b>{{Number1 + Number2}}</b>.
</div>
</body>
</html>
Demo
