title: Which ISO format should I use to store a user's language code?
body: <p>Should I use ISO 639-1 (2-letter abbreviation) or ISO 639-2 (3 letter abbrv) to store a user's language code? Both are official standards, but which is the de facto standard in the development community? I think ISO 639-1 would be easier to remember, and is probably more popular for that reason, but thats just a guess.</p>
  
  <p>The site I'm building will have a separate site for the US, Brazil, Russia, China, &amp; the UK.</p>
  
  <p><a href="http://en.wikipedia.org/wiki/ISO_639" rel="noreferrer">http://en.wikipedia.org/wiki/ISO_639</a></p>