Multilingual website? Make sure you use hreflang tags to indicate to Google what language a page is in; proper usage of these tags can improve search engine positioning for your multilingual sites.
You can also mark content for a particular country.
The tags should only be used when the same content is available in more than one language. All of the languages available should be listed together as a complete set in the header. For example, on a French page you would not have only:
Make sure that the pages you are tying together have the same content – although in different languages of course. Confusing Google with mis-matched sets of pages will hurt rather than help.
We use the WPML WordPress plugin, which adds the tags automatically so as to avoid any mis-matching. It also allows manual locale selection.
For more info on how WPML handles the hreflang tag, and for general information on how to use Google’s Webmaster tools to check that everything is working correctly, please read WPML’s developer information article on hreflang tags.