jquery AJAX

HTML

<form method="post" id="form">
<div id="json"></div>
<div id="xml">
    User: <span id="userid"></span>
    <input id="name" type="text">

    Password: <span id="sessionid"></span>
    <input type="text">    
</div>

<button id="submit">Login</button>
</form>

CSS

#html, #json, #jsonp, #xml, #form {
    border: 1px dashed #ccc;
    margin: 10px 0;
}
#html img {
    width: 50px;
}
#user-login {
    background-color: #fff;
    padding: 4px 7px 2px 7px;
}
#user-avatar {
    float: left;
}
#user-avatar .avatar {
    border: 1px solid #ddd;
    padding: 1px;
    width: 24px;
}
#user-overview {
    margin-left: 36px;
}
#user-overview h1 a {
    font-size: 13px;
    text-decoration: none;
}
#user-overview h1 a:hover {
    text-decoration: underline;
}
#user-overview p {
    color: #666;
    font: italic normal 10px arial, sans-serif;
}
#user-overview p a {
    color: #333;
    text-decoration: none;
}
#user-content {
    background: #fafafa;
    filter: progid:DXImageTransform.Microsoft.gradient(GradientType=0, startColorstr='#fafafa', endColorstr='#efefef');
    background: -webkit-gradient(linear, left top, left bottom, from(#fafafa), to(#efefef));
    background: -moz-linear-gradient(top, #fafafa, #efefef);
    border-top: 1px solid #eee;
}
#octocat {
    background: url(data:image/png;
    base64,...

JavaScript

$('#submit').click(function (evt) {

   //  console.log($('#name'));
     $('#json').append('hello');
      
     $.ajax({
            url: '/echo/json/',
            dataType: 'json',
            type: 'POST',
            data: {
                json: JSON.stringify("Hello");         
            }           
        }).done(function (data) {

            $('#json').append('hello');
});
  });