Pathanjali's yoga came to be known as Ashtanga yoga or Raja Yoga. After Pathanjali, especially after the advent of puranic Hinduism, several systems of yoga came into existence such as Hatha yoga, Gnana yoga, Bhakthi yoga, Karma yoga, Kundalini yoga, Kriya yoga, the latest one being the integral yoga of the 20th century systematised by the sage of Pondichery, Aurobindo.

These several systems except the integral yoga came into existence as both sankya yoga and Pathanjali's yoga exacted too much of a mental and moral discipline from the sadhakas (students) of yoga. Moreover there were differences in temperaments and talents among them and something had to be done to accommodate the different degrees of moral and mental capacities of these sadhakas (students), besides meeting the exigencies of social, cultural and religious needs and changes.

In the process of this accommodation many moral lapses and mental perversions have taken place, twisting and misinterpreting the ideology of the old yoga and introducing many abominable practices in utter disregard of all moral and ethical values. Mesmerism, hypnotism and magic paraded under the garb of yoga and many unscrupulous men are seen going about commercialising their capacity to make a living.

The integral yoga of Aurobindo retains all the salient and ethical features of the old yoga system. But its main aim appears to be to divinise man and make the earth a paradise for him to live through the grace of the supramental force.

People often mistake yoga asanas, the various physical posture in the nature of physical exercise as the cult of yoga. These asanas constitute but one among the eight steps in aid in the practice of yoga. The most vital part in the practice of yoga is the moral discipline that includes truthfulness, chastity, non-violence, right conduct and right living. For the student of yoga it is a bold adventure of the spirit into the realms beyond the thought or imagination of the common man.