According to Rishi Patanjali, there are eight stages or components of Yoga. They are follows:

• Yama, Forbearance
• Niyama, Observance
• Asana, Posture
• Pranayama, Regulation of Breathing
• Pratyahara, Abstraction
• Dharana, Concentration
• Dhyana, Meditation
• Samadhi, Trance

The first five components or stages out of the above-mentioned eight stages are connected with external Yogic exercises, and the remaining three are related to internal Yogic exercises. All these stages have been further divided as follows:

1. Yama:
Forbearance. It has the following five components:

• Ahimsa (Non-violence)
• Satya (Truth)
• Astey (Conquest of the senses of mind)
• Aprigraha (Non-receiving)
• Brahamcharya (Celibacy)

2. Niyama:
Observance: These two have the following five stages of components :

• Shauch (Obeying the call of nature)
• Tapa (Penance)
• Santosh (Contentment)
• Savadhyaye (Self-study)
• Ishwar Paridhan (God-consciousness).

3. Asana:
Posture The number of Asanas is as much as the number of birds. Asanas should be performed according to the capacity of the body. They should be done by exhaling air through breathing, stopping breath and re-Breathing everyday.

4. Pranayama:
Regulation of Breathing. Pranayama is a part of meditation. It has the following three parts:

• Purak (Inhalation)
• Rechak (Exhalation)
• Kumbhak (Holding of Breath): Holding breath and exhalation are called Pranayama (Regulation of breathing).

5. Pratyahara: 

Abstraction. Pratyahara means detachment of mind from all the vgorldly pleasures and comforts.

6. Dharana:

Concentration Dharanameans exercising control over our organs But it is very difficult to practise it.

7. Dhyana:
Meditation. When a person gains control over mind the state of Dhyana sets in. In this state, body and mind become like the flow of the river in which the currents of water have no effect at all.

8. Smadhi Trance:
It is the state of mind which starts with Dharana and ends with Samadhi. All these states have deep connection among them.The science of Yoga is a valuable contribution of India to the world. Yoga is gaining popularity at home and abroad. All the doctors and teachers of Physical Education acknowledge its utility. Yogic exercises are completely scientific in nature and in accordance with the structure of the body.