An important part of the Itihasas are the Puranas. The Puranas are the histories of the universe and contain many stories that took place on earth or even on other planets and dimensions, or in which superhuman powers are commonplace. As we pointed out earlier, Vedic knowledge often consists of information about things from beyond our own sense perception or experience. We can be assured of its authenticity because of the fact that many Vedic scholars such as Sukadeva, Maitreya, Madhva, Ramanuja, and others have reached spiritual perfection with the help of information found in the Puranas.

Each Purana is supposed to contain five basic subjects and in some cases ten. These include the creation of the world, its destruction and re-creation, the genealogy of the patriarchs and the demigods, the reigns of the Manus (who are the avataras in each duration of time known as a manvantara), and the history of the Solar and Lunar dynasties. Many of them also include descriptions of the activities of the incarnations of God, as well as the great sages and devotees of God. One thing that may seem somewhat confusing is that the stories are not in any particular chronological order and may be related at any time according to need. This is primarily due to the fact that the Puranas are generally related in a dialogue of questions and answers between sages and saints, or masters and disciples. Then the histories and stories are related in the answers.

Other subjects included in various Puranas are geography, astrology, use of military weapons, organization of society, duties of different classes of men, characteristics of social leaders, predictions of the future, law of reincarnation and karma, analysis of the material elements, symptoms of consciousness, how the illusory energy works, the practice of Yoga, Meditation, Spiritual Experiences, Realization of the Absolute, etc.

The Puranas explain more clearly and completely the spiritual philosophy found in the four original Veda samhitas. Thus, they especially are meant for all classes of people. Since all men are not on the same level of consciousness and are spread over many different types of thinking, feeling and desiring, the Puranas are divided so that any class of people can take advantage of them and utilize them to get out of the material entanglement either gradually or rapidly. So, depending on their position in life, people may use the particular Puranas that are most suited for them.

The Puranas are divided into two main groups consisting of :

Primary : Mahapuranas
Secondary : Upa Puranas

The Mahapuranas are divided into three groups :

One group considered to be related to the mode of tamo-guna, or the lower nature, consists of the Linga, Skanda, Agni, Matsya, Kurma, and Shiva (or sometimes the Vayu) Puranas. These are related to Lord Shiva.

The next group is usually related to Lord Brahma and is considered connected with raja-guna, the mode of action or passion. These consist of the Brahma, Brahmanda, Brahma-vaivarta, Markandeya, Bhavisya, and Vamana Puranas.

The third group relates to Lord Vishnu with satya-guna prevailing, which is the mode of purity or goodness. These are the Vishnu, Bhagavata, Narada or Naradiya, Garuda, Padma, and Varaha Puranas.

The Upa Puranas consist of eighteen sub kinds : Sanatkumara, Narasimha, Naradiya, Shiva, Durvasasa, Kapila, Manava, Ausanasa, Varuna, Kalika, Samba, Nandi, Saura, Parasara, Aditya, Mahesvara, Bhagavata or Bhargava and Vasistha.