People
Pictures of people that capture raw emotion are always my favorite. Sporting events are great places to capture those shots. I also get a few from my family and pose a few for friends Sr. pictures or just to mark the passing of time.
Naturally Made
Pictures of things I see that are lovely or powerful or just for history - Made by the hand of God or man.
Animals
Animal pictures are much harder to take than some subjects but just like capturing that moment of thought on a child's face capturing any living creatures inflections can be very rewarding if tempered with much patience.