February 23, 2010Playing around with Google's great Webmaster Tool I noticed that a site I'm working on had several URLs containing the same meta description. This was caused not by generic meta data, but rather that Google saw a page reposted with a querystring for toggling an archive tree as a seperate page. This makes two or more pages with identical content which isn't a good thing search engine-wise.
Enter the canonical link
You can tell Google which page that should be used when indexing. This is done by adding a link element to your page's header.
<link rel="canonical" href="http://www.mysite.com/blog.aspx" />This would divert indexing of URLs like http://www.mysite.com/blog.aspx?archive=feb.
Read a far better explanation at Google's blog, how to specify your canonical meta data.