Characteristics - Exercise to music normally using low weights with many repetitions and variety of exercises, such as lunges and squats.
Pilates?
Fitness - Body and the mind, like yoga.
Characteristics - A series of core movements focusing on the quality of the exercise rather than the quantity. So less vigorous but working on a range of movement. Also focuses on correct breathing.
Yoga?
Fitness - Body and the mind.
Characteristics - Emphasis on quality of exercise, holding the correct position with full range of movement and balance, and breathing correctly.
Spinning?
Fitness - Aerobic fitness.
Characteristics - Aerobic and anaerobic cycling on a stationary bike to music.