The Vedas are the fountain head of the spiritual literature of our Sanatana Dharma. These Vedas have six ancillary texts/ Sastras called the Vedangas / limbs of Vedas. These sastras are essential to be studied as part of the learning the meanings of Vedas.
In addition to the above, there are six more sastras called Darsanas, or treatises of philosophy, which mainly concentrate on the purpose of life, and also on the ways and means of attaining Moksha / salvation. The Darsanas include Samkhya, Yoga, Nyaya, Vaiseshika , Poorva Mimamsa and Uttara Mimamsa. Some of the topics covered in these texts are- nature of jiva, Paramatma, creation, maintenance and dissolution of universe, rules and regulations of varnas, etc. It is expected that an integrated knowledge of all these makes the life of the individuals happy , both in this world and beyond also.
The book “Shad Darsanamulu” gives a comprehensive view of all the six Darsanas of our Vedic literature.