Chandogya Upanishad is one of the oldest Upanishads written on the Vedic Brahmana period about ninth to eighth century B.C. Chandogya Upanishad is associated with Sama Veda. It is ranked ninth in the Muktika canon of hundred and eight Upanishadas. Chapter Six of Chandogya Upanishad consists of sixteen khandas.

1st Khanda
The 1st khanda deals with the non duality of the Self. Svetaketu the grandson of Aruna at the age of twelve went to stay with his teacher to study the Vedas. He then returned when he was twenty-four. His father then teaches him about the real Self.

2nd Khanda
In the second khanda Svetaketu`s father teaches him about the Supreme Brahman, the cause of the Universe. He tells him that at the beginning nothing existed. Then the Brahman thought of growing hence, he began creating the universe. He created the fire, water and other elements.

3rd Khanda
The 3rd Khanda states about the threefold development; those that take birth from an egg, those born from a living being and those that takes birth from a sprout. The deity next thought of entering into those three deities to develop names and forms.

4th Khanda
The 4th Khanda further explains about the threefold development. It is a continuation of 3rd Khanda. It describes about the different colours and the ways they are manifested into different elements.

5th Khanda
The 5th Khanda deals with the threefold nature of food. According to it the food when eaten becomes threefold. The gross particles become excrement, the middling ones flesh, and the fine ones the mind. Water when consumed becomes threefold. The gross particles become urine, the middling ones blood, and the fine ones respiration i.e. Prana. Heat when consumed becomes threefold. The gross particles become bones, the middling ones marrow, and the fine ones speech. The mind thus, constitutes food, the Prana of water and speech of heat.

6th Khanda
The 6th Khanda discusses about the physical nature of the mind, the prana and speech. It explains, when curd is churned, its fine particles rise upwards and form butter. Similarly the finest part of the food becomes Prana. The finest part of heat becomes speech.

7th Khanda
The 7th Khanda discusses about the how the mind consists of food. It says that humans consist of sixteen parts. Svetaketu`s father here explained to him that the mind consists of food, the Prana consists of water and speech consists of fire.

8th Khanda
The 8th Khanda describes about sleep, hunger, thirst and death. When a person is into deep sleep he becomes united with Pure Being. The water is thought to be the most important of food. When a person departs his speech merges with the mind, his mind in his Prana, his Prana in heat and the heat in the Highest Being.

9th Khanda
The 9th Khanda states about the absence of individuality in deep sleep. When bees collect honey from different flowers and store in one place, it cannot be distinguished from where they were collected. Similarly, when all the creatures unite with the Supreme Being they cannot be distinguished from where they appeared.

10th Khanda
The 10th Khanda states about the absence of particularized consciousness during sleep. According to this the eastern rivers flow towards the east, the western rivers flow towards the west but they all mingle with the sea. They then cannot be distinguished from where they appeared. Similarly, when all the creatures unite with the Supreme Being they cannot be distinguished from where they appeared.

11th Khanda
The 11th Khanda states about the indestructibility of the Jiva. According to it when the body is forsaken by life it dies, but the life does not die. That particle which is the soul of this body is Truth. It is the Universal Soul, the real Self.

12th Khanda
The 12th Khanda deals with the birth of the gross from the subtle. The seeds of a tree contains nothing but truly from there rises the great nyagrodha. Thus, when nothing can be perceived from that very essence this great nyagrodha arises. In that subtle essence exists the Prana, the real Self.

13th Khanda
The 13th Khanda deals with the invisibility of an existent object. According to this Svetaketu was instructed by his father to place salt in water. Svetaketu did as he was told and brought the salt dipped in the water to his father. His asked him to find the salt from the water but he could not as it has completely dissolved in it. He was then instructed to sip the water first from the surface, then from the middle and then from the bottom. It was all salty in taste. It is the same case with the body. Even if the Prana is not visible it is present in the body. This is the ultimate truth.

14th Khanda
The 14th Khanda deals with the means of self knowledge. The teacher is the ultimate means of knowledge. Only by attaining him a pupil can obtain the true knowledge.

15th Khanda
The 15th Khanda states about ultimate liberation. When a man is laid up with a mortal illness, his relations surround him to render him service and enquire whether he is able to recognise them. He recognizes them until his speech merges into his mind, his mind merges into his life, his life merges into heat, and the heat into the Supreme Deity. When his speech is merged into his mind, and his mind is merged into his life his life is merged into heat and heat into the Supreme Deity, he cannot recognise them. That particle which is the soul of all this is Truth, it is the Universal Soul.

16th Khanda
The 16th Khanda states about liberation for the knower of Brahman. One who is aware of the Brahman, the Real Self becomes immortal is liberated from the cycle of birth and death.