Posted by Bob Jonkman on April 28th, 2009
Valid HTML is not just useful for browsers. One of the big benefits of having valid HTML is that search engines can properly index your site. If the HTML is invalid, then the search engines may index you incorrectly, or not at all. Google isn’t the only search engine out there, and you want to drive as much traffic to your site as possible.
There appears to be some contention whether valid HTML makes a difference to search engines or not. Some say it doesn’t; or that it depends on the search engine; others have evidence it matters a lot.
Even if you’re not coding by hand, I urge you to have a look at HTML Dog, a set of tutorials on creating valid HTML. When things don’t work as expected you can turn here for examples in XHTML.
If you’re going to be using an editor for your Web pages, pick an editor that creates proper HTML code. Abandon FrontPage. I suggest using KompoZer, which is based on the same rendering engine as Firefox (Gecko).
You should also be checking your pages in Opera, which is a browser that is even better for standards-compliance than FireFox. The Chief Technology Officer for Opera is the same guy that wrote the Cascading Style Sheets specification, so it has a good pedigree.
If you’re using Firefox then be sure to check your pages with the HTML Validator addon:
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