HTML What are the benefits to having valid xhtml?

Are there any benefits to having valid xhtml on your pages, besides knowing that all of your tags are closed and all of your special characters are escaped?

And to go a step further, if you can answer this - is there any benefits to using a particular DOCTYPE, other than certain attributes are available to you?

 

Most of the time, if you need help with the site in a different browser, the first thing they want is validation or errors and warnings removed. Many times this will correct the problem. If not, it is the first step.
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advantages of validation
http://w3cvalidation.net/advantages-of-w3c-validation.html
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Doctype
http://www.alistapart.com/articles/doctype/
http://24ways.org/2005/transitional-vs-strict-markup
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falcon

 

Some validation checkers:

WDG HTML Validator

Test your Website using free HTML validation and spell check

Validation Tools

The W3C QA Toolbox - Validators, checkers and other tools for Webmasters and Web Developers

CSS Validation Checker Tool, Website Cascading Stylesheet Validator, Style Sheet Checker
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hope this helps
falcon