Those concerned about the effect of duplicate content on search engine optimisation can now take advantage of a new tag designed to minimise this problem.
Launched by Google, Yahoo! and Microsoft, the ‘canonical’ link tag can be used to specify which URL webmasters want search engines to concentrate on when the site contains a lot of similar content pointed to by many URLs.
Microsoft said it will launch the new tag in the near future. Yahoo! is expected to roll it out in the next few months, meanwhile.
"If your site has identical or vastly similar content that’s accessible through multiple URLs, this format provides you with more control over the URL returned in search results," say Joachim Kupke, senior software engineer, and Maile Ohye, developer programs tech lead at Google in a blog post.
"It also helps to make sure that properties such as link popularity are consolidated to your preferred version."
Google will "strongly" honour the new tag, Mr Kupke said, stating that the preferred URL will be taken into account in addition to other factors when it is working out the most relevant page to display in search listings.