Patanjali uses the word astanga yoga meaning eight components of yoga. Patanjali explains astanga yoga with its three aspects or divisions, namely external, internal and innermost The practical aspects of yoga begin with yama to cleanse the organs of actions; niyama for control of the senses of perception; asanas for keeping the body healthy; pranayama for right usage of energy; pratyahara to obtain stability in mind; dharana for clarity and maturity in intelligence; dhyana to cultivate humility by subjugating ego and pride; and samadhi for a composed state of equanimity. The eight components of yoga are summarised as follows:
Yama(External discipline): The five external disciplines are not harming, truthfulness, abstaining from theft, celibacy, and not being acquisitive.
Niyama(Internal discipline): The five internal disciplines are cleanliness, contentment, intensity, self-study, and dedication towards God.
Asana(Posture): The posture for meditation should be comfortable and steady. One has to achieve mastery over the asana or posture which is one of the components of yoga.
Pranayama(Breath regulation): The pause in the flow of breath is called pranayama. The pause may be either inhaling and retaining the breath, or exhaling and retaining it, or it may be at any time.
Pratyahara(Withdrawl of senses): Pratyahara means withdrawl of senses. In the yogic stage when the mind uncouples from external objects, the senses do likewise, this stage is called Pratyahara. Pratyahara is a state where the scattered thoughts and thinking processes that motivate the organs of actions, senses of perception and the outgoing mind are braided together to co-ordinate and become one. It is a unity as external thoughts and objects are associated as one. In short, pratyahara is the way of silencing all functions of the brain. With this, the discerning mind becomes free from fluctuations and temptations. Living in the house of consciousness is pratyahara.
Pratyahara acts as a bridge to cross from the external sheaths of investigation, cleansing the inner sheaths for further investigation and then refiltering to dry out all the impurities where passivity and pensiveness of both body and mind can be experienced and noted. Pratyahara is a place to establish stability in yama, niyama, asana and pranayama and them to move with attention towards dharana, dhyana and samadhi. Pratyahara is a meaningful pause between bahiranga and antaranga samyamas. This pause indicates the crucial standard of the sadhaka. These two pauses in the form of virama pratyaya in samadhi and pratyahara in astanga yoga may cause one to be cought in the net of success. This in turn may cause one to fall into the trap of avirati leading towards the unsettled state. Pratyahara is the culmination of the process of indriyajaya, the mastery over the eleven indriyas.
The individual mind which was controlling the senses on one side and the seer on the other, transforms into a single state of attention. This mind transfigures into cosmic mind, the first principle of mula prakriti. When this single mind is submerged in the root of nature, the seer shines on his own.
Dharana: Dharana is focusing the mind on a object or region.
Dhyana: When the entire perception is directed towards that object it is called dhyana
Samadhi: When the essential nature of the object shines forth devoid of its own form-empty, it is called samadhi.