Scopes are controllers specific. If we define nested controllers then child controller will inherit the scope of its parent controller.

<script>

var mainApp = angular.module("mainApp", []);

mainApp.controller("shapeController", function($scope) {

$scope.message = "In shape controller";

$scope.type = "Shape";

});

mainApp.controller("circleController", function($scope) {

$scope.message = "In circle controller";

});

</script>