I'm in my third year now, but I decided not to join a frat/fraternity.
I know people in a whole bunch of different fraternities, and one thing I've noticed is that the ones that are what I would consider "better" (community service oriented, and actually about making real and lasting friendships that aren't based on hazing) make a difference between "frat" and "fraternity." They describe a frat as what you see in the movies, with hazing and excessive drinking, but maintain that they aren't a frat, but rather a fraternity. They say they're different from that common stereotype.