What is the best Birth control for a woman?

My current g/f is planning on getting BC for the first time, and is trying to do research on it. She asked for me to help, so I figured this would be a good place to go. Now I’ve had g/f’s on BC before, but my knowledge of them is pretty low. SO, could any knowledgeable people (especially women who use/have used BC) list what is your favorite BC and why? And/or the pros/cons of the various female BC methods (shot, pill, etc).