Error: [ng:areq] from angular controller

Question

This is a long shot, but has anyone seen this error before? I am trying to add \'Transporters\' using express, angular and mongoDB. I get this error whenever I access a page

Answer 1

// include controller dependency in case of third type

 var app = angular.module('app', ['controller']);

// first type to declare controller // this doesn't work well

var FirstController = function($scope) {
    $scope.val = "First Value";
}

//Second type of declaration

app.controller('FirstController', function($scope) {
    $scope.val = "First Controller";
});

// Third and best type

angular.module('controller',[]).controller('FirstController', function($scope) {
    $scope.val = "Best Way of Controller";
});