What do you want to know about him?

(I loathed Kantian ethics and having to take a course on Kantian philosophy, but it did stick with me.)

If you just want to know about his philosophy, he's most famous for his "categorical imperative" theory. Basically its the "driving force" behind humans acting on some unsaid moral/ethical code. Basically it boils down to whether or not your action in a particular instance is self-contradictory (in which case the action is immoral) and/or if the action is generalized to any situation that said action would be ideal for all parties.

The most famous example I can remember is that of a neighbor's home being burglarized. You don't like the neighbor, and you have nothing to gain from reporting the burglary to the police since you don't like the neighbor. If you don't report the burglary to the police, you are inherently performing an immoral act, as even though the action is not self-contradictory, it is not an idealized action for all parties, namely your neighbor or yourself potentially in the future. The burglar is already performing an immoral action and is therefore exempt from the concept of "all parties" under the second part of the categorical imperative.

Oh and what Lila said about using people as a means to an end.