Ashtanga / Power - An athletic, fast paced yoga that is not recommended for beginning students.   The core emphasis is on Vinyasa - incorporating Ujjayi Pranayama and linking the breath with each movement throughout the practice.   Ashtanga has a rigid sequence of poses and uses an engagement of Mula Bandha.   Power yoga is a derivative of Ashtanga using a more creative sequencing of poses.

Bikram / Hot - an athletic, physically focused yoga practiced in a room heated to 100+ degrees.   Bikram is a rigid sequence of 26 poses, while Hot yoga incorporates more of a variety of poses.   Beware: Bikram instructors often behave like drill seargents and encourage their students to push hard which often leads to injuries.  

Iyengar - a technical yoga with a strong focus on alignment and a heavy use of props.   Iyengar yoga also emphasizes the therapeutic properties of the poses.   A good choice for the beginning student.

Kripalu - an therapeutic, gentle and spiritually focused yoga with clear alignment and a three stage approach incorporating Pratyahara (inner focus) and Dhrana (meditation) within the yoga poses. A good choice for the beginning student.

Kundalini - an dynamic, esoteric and energizing yoga incorporating pranayama, movement, asana, and chanting.   The aim of Kundalini is to invoke the dormant spiritual energy at the base of the spine.

Sivananda - an traditional approach to yoga with a ridgid class structure of asana, pranayama, meditation and relaxation.   Sivananda yoga teaches many advanced poses making it not the best place for a beginning student.