Yes. It's a good source of information about languages of the world and SIL (the organization behind it) is the authority for ISO 639-3 language codes[1]. Some experts criticize[2] their approaches on what should be classified as a language and what should not (and should remain in the realm of dialects) as well as religious missionary background of the organization.
[1]: http://www-01.sil.org/iso639-3/
[2]: http://www.nytimes.com/2005/07/19/science/how-linguists-and-...
Edit: Correct footnote numbering.