This page is designed to tell commercial web developers why they should develop StandardsCompliant web pages.

Why should I make my web site compliant?

Because the IT department of your biggest clients are changing away from InternetExplorer in droves. Windows users tend towards MozillaFirefox or Opera, Mac users may be using MozillaCamino or Safari. Linux users have probably been using Mozilla forever.

The percentage of people using a non-IE browser is estimated to be between 5% and 15%, depending on who you ask. You wouldn't tolerate a phone system or secretary that turned away 10% of potential customers who ring you...

Dos and don'ts

• Don't use "document.all" in your JavaScript
• Don't use MSXMLDOC
• Don't develop your CSS padding/margin/box model by only testing in IE
• Do test your HTML pages against http://validator.w3.org/ (or the free "sgmlnorm" program)
• Don't put stuff in a table without <td> tags around it (IE displays it, Moz might not)
• Don't use markup purely because its default display suits what you want. Use markup that's suitable to the content, then style it using CSS, instead.
• Don't create browser detection pages that lock out browsers you think won't work, or browsers you don't recognise. New browsers and versions come out all the time, and you never know when one of them will be fixed.
• Don't put tooltips in 'alt' attribute. They belong in 'title'.

There's a great guide on the specifics at http://nexgenmedia.net/evang/iemozguide/. See also the Mozilla Web Author FAQ.

Should I support Netscape any more?

If you support Mozilla, you're supporting Netscape 7 and up. These days it's realistic to drop support for any version of Netscape 4 or below.