2 x 2 Framing Question

I see a lot of folks using 2 x 2 's for framing for counters and cabinets. Great idea, I like it. Just wondering about joints. It looks like everyone uses simple butt joints, but I am sure there is more to it than that. I would worry about the 2 x 2 splitting if I ran a screw in it. All help and especially pictures are appreciated.