Writing forward-compatible websites

JavaScript

window. onfoo

onclick, onmouseover HTML document window

<div ></div>

div ownerDocument var ownerDocument

DOM HTML5

window

<script>
  function localName() {
    alert(" localName ");
  }
</script>
<div ></div>

"use strict;" ECMAScript

JavaScript

"filter" in body.style true Microsoft Internet Explorer window.event DOM DOM onload onreadystatechange

UA

User Agent

UA

UAUser Agent

Firefox Aurora Beta Firefox Aurora Beta

UA

FirefoxChrome Safari WebKit Opera Internet Explorer

X X Y X Y

UA

Vender-prefix

-vnd make-it-pretty sometimes

<style>
  .pretty-element {
    -vnd-make-it-pretty: sometimes;
    make-it-pretty: sometimes;
  }
</style>

CSS API

>

> Tag Tag HTML5 HTML5

<form action="http://www.example.com">
  <input type="submit" value=""
</form>

input Tag >

CSS