Hot yoga and Bikram are separated by one thing: copyright issues. Choudhury Bikram has copywritten his particular style of yoga. Bikram yoga actually consists of 27 postures, done sequentially in a room heated to 105 degrees. No worries about loads of bacteria here though, both hot and Bikram yoga studios are equipped with fresh air flow vents so the air does not become stagnant.
Hot yoga can be done in a specialized room and has taken a new turn over the last several years. Hot yoga can include several varieties of yoga traditions done in a room heated up to 105 degrees. Many hot yoga studios have branched out and now offer hot Pilates, hot belly dancing, and even hot core classes.
The benefits of both hot yoga and Bikram yoga are similar, though Bikram claims to have the magic set of postures (27) done in the most effective order. Bikram is great for those who crave order in their workouts and like to know what's coming next.
Both hot yoga and Bikram provide wonderful detoxifying effects for the body, not only due to the heat, but also the twisting postures that are found throughout each practice. Call your local studio and obtain a free session or week to assess your tolerance for the heat before committing to this particular practice.