Cross browser question about HTML 5 doctype

Can I use the HTML 5 doctype in older browsers like IE 8 or 7? If n开发者_如何学运维ot what would be a good method to handle cross browser compatibility?

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A lot of people use and recommend the open source modernizr javascript library to handle these issues. You can code for HTML5 and modernizr will try to gracefully degrade for features not supported by the user's browser. As they say:

Taking advantage of the new capabilities of HTML5 and CSS3 can mean sacrificing control over the experience in older browsers. Modernizr 2 is your starting point for making the best websites and applications that work exactly right no matter what browser or device your visitors use.

It is high-quality enough to be used by Google, Microsoft, The Economist, About.com, The Knot, Good and Posterous.