Unknown provider: $modalProvider <- $modal error with AngularJS

Question

I keep receiving this error as I\'m trying to implement bootstrap Modal window. What could be the cause of it? I\'ve copy/pasted everything from http://angular-ui.github.io/

Answer 1

var ModalInstanceCtrl = ['$scope', '$modalInstance',  function ($scope, $modalInstance, items) { 
   /* copy rest of example code here */ 
}];