There are many different styles of yoga.
Although they are all based on the same postures, each has a particular emphasis.
Here is your "Quick Guide" to some common Yoga Styles:
ANUSARA - Light-hearted; Props often used; Strong emphasis on physical alignment
HATHA - Gentle; Slow-paced; Good introduction
ASHTANGA - Intense; Fast-paced; Set series of poses in single order
BIKRAM - "Hot Yoga"; Room is 100-103 degrees; Set series of 26 poses; Cleansing through profuse sweating
IYENGAR - Focus on body alignment; Poses held longer; Use of props encouraged
JIVAMUKI - Intense; Emphasis on meditation, and spirituality; Often includes chanting
KRIPALU - Style of HATHA; Emphasis on meditation, physical healing, and spirituality; Focus on looking inward
KUNDALINI - Emphasis on breath (prana); Rapid, repetitive movement; Often includes chanting
VINYASA - Movement synchronized to breath; Includes series of Sun Salutations