There are four main branches of yoga; Karma Yoga, Bhakti Yoga, Raja Yoga and Jnana Yoga. Each branch is simply a different path towards the same goal - attainment of truth. A yogi(ni) on a Karma Yoga path dedicates all work as an offering to God, without thought of personal reward. Bhakti Yoga is the devotional approach of yoga or the approach of true love. Raja Yoga is a scientific approach to yoga and is the most well-known approach in the United States . Raja Yoga has sub-paths - Hatha Yoga and Kundalini Yoga - where the prana or life force is mastered first and then the mind comes automatically under control. Jnana Yoga is the most difficult path; it’s the intellectual approach to spiritual evolution. In Jnana Yoga the mind is used to examine its own nature.