At his time PATANJALI succeeded to bring a system into the Yoga in his Yoga-Sutras which completed the system of the early Samkhya to the Isvara(God).
But most of this Yoga was described before in the Sandilya - Upanishad of Atharvaveda.
This eightfolded path is in detail described in the Yoga Yajnavalkya, and it has been mentioned in further hinduist texts like the Linga Purana, the Devi Bhagavatam 7.35, the Sivasamhita and the Hathapradipika.
"Ashtanga Yoga--Yama, niyam, aasan, praanayaam, pratyaahaar, dhaarnaa, dhyaan, samaadhi, theses are the eight limbs of yoga. A Guru takes a disciple into these one by one."(Shankaraycharya Swaroopanand Saraswati, The Illustrated Weekly of India, September 13, 1987)
Patanjalis Yogasutras had nearly been forgotten since the 11th century. This system was often little understood because he offered no special training-system with specific exercises except OM-Meditation, pranayama and asanas.
The eight steps of RAJA - YOGA are equivalent to step 1- 16 of the UNIVERSAL Path.
1. YAMA [ Tarot 1, 2 ] - Satya, Ahimsa, Brahmacharya, Aparigraha und Asteya
2. NIYAMA [ Tarot 3, 4 ] - Saucha, Santosha, Tapas, Swadhyaya and Ishwara Pranidhana
RAJA-Yoga has a kind of moral as its basis - and the study of the holy scriptures. Practices besides a change of lifestyle and of nutrition are singing of special mantrams!
The Hatha Yoga Pradipika mentions these steps in 'Asanas 16,17' too.
3. ASANA : Body-exercises like in Hatha-Yoga, the beginnings of Tai Chi Chuan or the first steps of KungFu-Training [ Tarot 5, 6 ]
Yogasutra 2.47 : 'prayatna-śaithilyānanta-samāpattibhyām' : By relaxing effort and fixing the mind on the infinite [asana is perfected]. This step consists actually also of meditations on the infinite (as also the buddhist Culasuññata Sutta teaches).
4. PRANAYAMA - Purification of the life-force (Prana, Chi) [ Tarot 7, 8 ]
The chinese energy-exercises (Qi-Gong, Circulation of Chi) have a similar effect
5. PRATYAHARA - Drawing back of the senses [ Tarot 9, 10 ]
6. DHARANA - Concentration [ Tarot 11, 12 ]
7. DHYANA ( Meditation ) [ Tarot 13, 14 ]
The meditation is now so deep that it is the forrunner of Samadhi.
8. ISHVARA - SAMADHI (God - Extasy) [ Tarot 15, 16 ]
"Engaged in the practice of concentration, uttering the monosyllable OM, remembering Me always, the yogi attains to the supreme goal." (Bhagavad Gita 8,13)
The Krama -Section of kashmir Shaivism practices a path similar to the Ashtanga - Yoga which requires first three double-stages.
“When you establish the internal reality of God Consciousness in Your soul, that is dharana. This dharana is not only to be established in internal God Consciousness but in all activities of the worldly life. This is true dharana." (Netra Tantra.)