The Canonical Tag—A Useful Tool for Split Testing:
Different from domain canonicalization is the “canonical” tag. Add this one to your SEO tool box as well. For other inside pages that you think may have duplicates, you’ll want to look into the “canonical” tag. This tag is officially being accepted and understood by all three main engines, Google, Yahoo and MSN Live/Bing. This is a tag that goes on the ‘duplicate’ head tag to direct to the ‘actual’ page. It only tells the robots, not website visitors, which URL to index. Unlike the 301 redirect, the visitors do not get redirected anywhere. This is a great tool for split testing because visitors don’t see a difference, web analytics software tracks the separate pages but search engines see it as one page.
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