The Yoga Sutras of Patanjali are a book of 196 aphorisms compiled by the sage Patanjali sometime between 100 BC and 200 AD. Patanjali in the Yoga Sutras presents the goal of yoga as 'the cessation of mental fluctuations' (cittavrtti nirodha).

In reference to the Bhagavad Gita classifications, Patanjali's yoga is a form of Raja yoga, as it seeks meditiation as the path towards the ultimate goal. Patanjali himself referred to it as "Ashtanga Yoga" ("Eight-Limbed Yoga"), from the eight steps he set out as the practical path towards attainment of enlightenment. This eight-limbed concept became a authoritative feature of Raja yoga from that point forward, and is a core characteristic of practically every Raja yoga variation (including Hatha yoga) taught today. 

Patanjali's Eight Limbs of yoga practice are: 

(1) Yama (The five "abstentions"): violence, lying, theft, (illicit) sex, and possessions

(2) Niyama (The five "observances"): purity, contentment, austerities, study, and surrender to god

(3) Asana: Literally means "seat", and in Patanjali's Sutras refers to seated positions used for meditation. Later, with the rise of Hatha yoga, asana came to refer to all the "postures"

(4) Pranayama ("Breath Control"): Control of prāna or vital breath

(5) Pratyahara ("Abstraction"): Reversal of the sense organs

(6) Dharana ("Concentration"): Fixing the attention on a single object

(7) Dhyana ("Meditation"): Intense contemplation of the true nature of reality

(8) Samadhi ("Liberation"): Super-conscious state of enlightenment

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