angular js: Error: $ is not defined in http post
<p>I'm trying to post values from a form. Form has two fields- name and email. I have setup the controller as well but when i try to post, error is shown.</p>

<pre><code>&lt;form name="save" ng-submit="sap.saved(save.$valid)" novalidate&gt;

        &lt;div class="form-group" &gt;
            &lt;input type="text" name="name" id="name" ng-model="sap.name" /&gt;
        &lt;/div&gt;

        &lt;div class="form-group" &gt;
            &lt;input type="email" name="email" id="email" ng-model="sap.email" /&gt;
        &lt;/div&gt;

        &lt;div class="form-actions"&gt;
            &lt;button type="submit" ng-disabled="save.$invalid || sap.dataLoading"&gt;Save&lt;/button&gt;
        &lt;/div&gt;
&lt;/form&gt;
</code></pre>

<p>My controller is:</p>

<pre><code>(function() {

    angular
        .module('myApp.saved', [])

        .controller('dataController', function($scope, $http) {
            var sap = this;

            $scope.post = {};
            $scope.post.login = [];
            $scope.sap = {};
            $scope.index = '';

            var url = 'save.php';

            sap.saved = function(isValid) 
            {
                if (isValid) 
                {
                    $http({
                      method: 'post',
                      url: url,
                      data: $.param({'user' : $scope.sap }),
                      headers: {'Content-Type': 'application/x-www-form-urlencoded'}
                    })
                    .then(function(response) 
                    {
                            // success
                            alert('success');
                    }, 
                    function(response) 
                    { 
                        // failed
                        alert('failed');
                    });
                }
            };

        });

})();
</code></pre>

<p>When i submit, $ is not defined is shown. I'm pretty much new in angular. Can anyone tell what all mistakes I made?</p>