Posicionamiento Web.

META Tags are used to establishe certain parameters about the page, like the language, title and description.

On the contrary to the popular believe that the more METAs the better, the more METAs the worst. As a matter of fact search engines pretty much disregard all those extra METAs, that only end up adding a bit more of extra weight.

¿What META TAGS should I use?

With these few tags you will be just fine:

<META name="keywords" lang="en" content="you keywords, comma separated" />
<META name="description" lang="en" content="Your web site description" />
<META http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
<META NAME="ROBOTS" CONTENT="ALL" />

The tags like "revisit" are completely ignored by the search engines, although you might want to include other ones.