Now let’s see what you can do to make your HTML better.

Use a DOCTYPE

Probably the most important tag in your HTML is the DOCTYPE. This is what will tell the browser how to deal with your page. Here’s an example of a full DOCTYPE:

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN"
"http://www.w3.org/TR/html4/strict.dtd">

Here is a list of recommended DOCTYPEs and a great article from Alistapart that explains how to fix your site with the right DOCTYPE.
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