Have you ever wondered about how Google index pages.  They don''t use <META> tags as much as they used to.

<meta name="robots" content="index, follow" <-Default behaviour->

Google understands the following values (when specifying multiple values, separate them with a comma):  Use name="googlebot" to only effect Google and not other search engines.

• noindex: prevents the page from being indexed
• nofollow: prevents the Googlebot from following links from this page
• nosnippet: prevents a snippet from being shown in the search results
• noodp: prevents the alternative description from the ODP/DMOZ from being used
• noarchive: prevents Google from showing the Cached link for a page.
• unavailable_after:[date]: lets you specify the exact time and date you want to stop crawling and indexing of this page
• noimageindex: lets you specify that you do not want your page to appear as the referring page for an image that appears in Google search results.

You can now also specify this information in the header of your pages using the "X-Robots-Tag" HTTP header directive. This is particularly useful if you wish to limit indexing of non-HTML files like graphics or other kinds of documents. More information about robots.txt

Here is the rest of what Google supports for meta tags.

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