There 8 kinds of yoga:
Bhakti Yoga.
Karma Yoga.
Jnana Yoga.
Raja Yoga.Mantra Yoga.Laya Yoga.Tantra Yoga. Hatha Yoga.
For explenations check this out this link:
http://www.yogaworld.org/yogas.htm Hatha YOGA, is usually the one that is mostly talked about in the western world, in association with exercise and helth.