There are more grinds for bowl gouges than there are manufacturers, but the image below gives a very good idea of the basic shapes.

My general policy in this glossary is to consider the images I lift from various sites to be "fair use" in that they are small amounts and intended for educational use, so somewhat exempt from the normal rules of copyright. Also, I just don't have the time and energy to do references; I spend all my energy on the entries in the glossary. BUT ... I've made an exception in this case because both Mr. Thompson and his tools are held in very high regard in the woodturning community, so here is a link to his site: Thompson Lathe Tools