I just read that in Wikipedia about Florida International: "The U.S. News and World Report currently ranks FIU as a fourth tier postsecondary institution in the National Universities category." Well, I am bit unfamiliar with the American higher education system. Could anybody enlighten me more about these whole "tier" system? Officially, which colleges are in the first tier? Then the second, the third, and the fourth? Is there any such thing like fifth tier, sixth tier, and so on? What actually differs those colleges? Between the different "tier"?