I love to do yoga!  I find it so relaxing!
I love yoga too! My mother in law teaches Hatha yoga.
What exactly is Hath yoga?
Hatha Yoga teaches you to master your body and mind. I believe it focuses on strength and mental focus.
Does it include 'Hot Yoga'?
Yeah, you can do Hatha during a hot yoga class. I think you can do most yoga as hot yoga. Hot yoga just denotes the condition in which you are practicing yoga. 
Are there dangers to Hot Yoga?
I would imagine the danger of heat exhaustion increases with Hot Yoga, but you will have that with any physical activity done in hot or humid conditions
What is your favorite yoga?
My favorite yoga is Hatha yoga. It is the one I am most familiar with. It is also very challenging. What is your favorite?