javascript - I have my code running on jsfiddle, but why can't on local computer? -
    as title said, code running on jsfiddle: http://jsfiddle.net/paopaomj/zggpn/   and copy code on local computer (edit brackets),but failed run, miss? (ignoring css style here)       <html>     <head>         <script type="text/javascript" src="http://code.jquery.com/jquery-2.0.2.min.js"></script>         <!--<script type="text/javascript" src="tools.js"></script>-->         <link rel="stylesheet" type="text/css" href="style.css">     </head>     <body>         <script>             $document.ready(function(){                 $("#command").keyup(function (e) {                     if (e.keycode == 13) {                         submit();                     }                 });                  var submit = function () {                     var commandel = document.getelementbyid("command");                     var command = command...