About a year ago I posted a Quick Tip titled Specify each HTML document’s main natural language. The reason is that software like screen readers can use this info to adjust the way they speak text.
But do they really do that? Well, it depends. You need to use a screen reader that supports language switching and can speak the natural languages of the document you’re viewing. One example of when it works as expected is VoiceOver for the iPhone and for the iPod touch.
More at: http://feedproxy.google.com/~r/456bereastreet/~3/5F77Ck5_zFA/