The practice of yoga is more than 5,000 years old and the name, ‘yoga’, is derived from the Sanskrit word ‘yuj’, which means to unite.  Basically yoga is a practice of uniting mind, body and spirit in a harmonious balance.  Don’t worry, you have to be a contortionist to enjoy the benefits of yoga, which include strength, flexibility, better breathing, heart health, better concentration, and less anxiety.
There are four essential types of yoga: Raja, Karma, Bhakti, and Jnana.  Numerous versions and variations have sprung from these and they can be overwhelming to the novice.   Here is a list from the Ministry of Tourism and the Government of India that can help you determine which is right for you.

The 4 Essential Types of Yoga
Raja Yoga is the path of (physical and mental) self-control. Raja means, "king", and Raja Yoga is considered the complete yoga because it focuses on controlling both the mind and body in order to attain enlightenment. Absolute mental control, based on the Eight Limbs of Yoga, discussed in Patanjali's Yoga Sutras, is the mental goal, and this is achieved through meditation, concentration, and breathing. Hatha Yoga, the most popular branch of yoga, is the physical aspect of Raja Yoga. It considers the body as the vehicle for the soul, and uses physical postures (asanas), breathing techniques (pranayamas) and relaxation to bring the body to a perfect state of health. This includes harnessing the life force called prana. Within Hatha Yoga, there are many styles, including Ananda, Ashtanga, Bikram, Integral, Iyengar, Kripalu, Kundalini, Sivananda, and Viniyoga. Most of these are named after the person who developed the teaching style.

Karma Yoga is the path of actions. The Karma Yogi seeks to attain enlightenment through right actions, thoughts and deeds, and selfless service without thought of gain or reward.

Bhakti Yoga is the path of devotion. Those who practice Bhakti Yoga, through prayer, worship, and ritual, see the Divine in everyone and everything they encounter, thereby developing acceptance and tolerance for all.

Jnana Yoga
is the path of knowledge. This seeks to unify intellect and wisdom through questioning, meditation, and contemplation. It is considered to be the most difficult path, because it requires an open, curious mind and acceptance of an existence beyond doctrines. Before practicing Jnana Yoga, the student needs to have integrated the lessons of the other yogic paths - for without selflessness, love of God, and the strength of body and mind, the search for self-realization is nothing more than an exercise in philosophy.
While all 4 types of yoga seek to balance the body, mind, and spirit, they go about it in various ways, differing in how asanas are done and where the attention is focused. Each is suited to a different temperament or approach to life. All the paths lead ultimately to the same destination - to union with Brahman or God - and the lessons of each need to be absorbed if true wisdom is to be attained. The beauty of yoga is that you can dip as far as you like into the pond and still receive some benefits. The deeper you go, the more profound these will be.

Dynamic Living Magazine Issue Vol. 1  Jan/Feb 2011 The End