Generally, most informed sources will agree that there are six different branches of yoga practice, and these branches include hatha, bhakti, raja, jnana, karma and tantra yoga. Each branch is characterized by a different kind of practice, and not all of these are the typical physical exercise form of yoga that most people think of when they think of yoga practice. For example, hatha yoga focuses on the physical practice of yoga poses, while karma yoga is philosophical in nature, and raja yoga takes more of a meditative practice.
Hatha, the branch that is focused on physical poses, is perhaps the best known form of yoga. There are divisions within hatha yoga, such as Bikram, ashtanga or vinyasa yoga. These different schools of hatha yoga should not be confused with the main branches, which go above and beyond physical poses.
Yoga branches can be quite spiritual in nature. For example, bhakti and karma yoga are both concerned with selflessness, albeit in different ways. Tantra yoga may be the most misunderstood branch of yoga practice, thanks to its association with unusual sexual practices.