The Six Astika Darshanas:- Vedic Samhitas may  be seen as the roots the Indian philosophical tradition. The Brahmanas, Aranyakas  and  Upanishads  may  arise  from  that  roots. Then followed the multiple philosophical 'schools' in the post-Vedic era. Interestingly, the authority of these schools  is derived  from  their  adherence  to the Vedic scriptures. Although, they all are secondary to  the  Vedas  and  Upanishads  themselves, each  major `school` is presented not in the form of a long and rigorously argued treatise but as a series of  terse  statements, known as Sutras. Sutras  are  the  coded  medium  to  convey  knowledge  in different  ways. The  traditions  of interpretation, which are based upon these texts, are known as Darshanas. Sutras, like shruti are believed  to be verbal expressions of truth or realization.

Darshana  denotes  a  system  of  philosophy,  or  doctrine  in  the  sense of a treatise or an enquiry into truth or reality. There  exist  a  semantic  distinction  between  darsana  and  darsana  Shastra. The  Indian  philosophers consider philosophy both as darsana, the vision of truth; and darsana-shastra, the means  to  attain  it. There are six principal Astika or  Vaidika  darsanas,  which  embody  the  firm  conviction  in Veda. Apart  from  that  are Darsanas called Nastika ('non-orthodox') or Vedavahya (`outside the Veda`), which do not explicitly align them with the belief that the Vedas are infallible, revealed documents.

The Six Astika Darshanas are:
1. The Vaisesika darshana, founded upon the Vaisesika-Sutra of Kanda.
2. The Nyaya darsana, founded upon the Nyaya-Sutra of Gautama.
3. The Samkhya darsana, founded upon the Samkhya-Sutra of Kapila.
4. The Yoga Darshana, founded upon the Yoga-Sutra of Patanjali.
5. The Purva-mimansa Darshanas, founded upon the Mimamsa-Sutra of jaimini.
6. The Uttara-Mimansa or Vedanta darsana,  founded  upon  the  Vedanta-Sutra  (or Brahma-Sutra)  of Badarayana.

Hatha-yoga  (a part of  Saiva  tradition) views itself as being thoroughly Vaidika. This fact is something, which is implicit within the general philosophy of  the  hatha  treatises, and  even  more  explicit  in  the  codes  of  ethical conducts as prerequisite for the yoga. The  interpretation  of  these  Sutras  is  difficult task  in  itself  due  to  the extremely complex format of sutras where by the maximum amount of meaning is condensed  into  the  minimum number of words. Each  word  and  phrase  contains  various  possible  interpretations. The  Darshanas  have  a tremendous  amount  in  common  and  they  are  all  directed  towards  a  "goal  of  human  liberation  or   Self-realisation". The intra and inter conflicts between various Darshanas can be regarded  as  the  subjective  choice available for the person or seeker.

Indian  philosophy  is  much  deeper  rather  than  "the  knowledge  for  the knowledge sake." The philosophical enterprise here acts as a method for cultivating virtue and  self-understanding. It  is  for  this  reason  that, Indian philosophical systems or Darshanas may be referred as Moksha-shastra. Moksha means 'deliverance',  'release' or 'liberation' and shastra is the 'teaching' or 'doctrine' for achieving that end.