Answer:
Crosscut saw teeh are using for cutting "cross" or across the grain of the wooden plank. The edges are positioned at an angle.
Rip saw teeth work like chisels, slicing wood away instead of through it. Rip saw teeh don't have angled edges. They are designed for cutting straight along the grain of the wood.
I hope this information was of any help to you. Cheers! (: