Hinduism is referred to as Sanathana Dharma, the eternal faith. Hinduism is based on the practice of Dharma, the code of life. Hinduism has no founder.

While religion means to bind, Dharma means to hold. What man holds on to is his inner law, which leads from ignorance to Truth. Though reading of the scriptures (saastras) would not directly lead you to self-realization, the teachings of the seers provide a basis and a path for spirituality. Despite being the oldest religion, the truth realized by the seers proves that the truth and path provided by Hinduism is beyond time.

Hinduism is more a way of life than a specific religion. In Hinduism one can find all religions of the world. Various religions like Buddhism, Sikhism emerged from it. The most important aspect of Hinduism is being truthful to oneself. Hinduism has no monopoly on ideas. It is open to all. Hindus believe in one God expressed in different forms. For them, God is timeless and formless entity. Hindus believe in eternal truths and these truths are opened to anyone who seeks them, even if he or she is ignorant of Hindu scriptures or ideas. This religion also professes Non-violence - "Ahimsa Paramo Dharma" - Non violence is the highest duty. True Ahimsa implies curtsey, kindness, hospitality, humanity and love.

Most of the Hindus do not know about their scriptures. They are aware of Ramayana, Mahabharata and Bhagavat Gita only. But we have lot of scriptures. Every Hindu must be aware of his/her scriptures. This is a small attempt to give the reader a brief knowledge about our scriptures.

The primary texts of Sanatana Dharma are

I. VEDAS
The oldest and the most important scriptures of Sanathana Dharma are the Vedas. Veda means knowledge. Vedas are apauruseya, which means they are not compilations of human knowledge. Vedic knowledge comes from the spiritual world, from Lord the Supreme Personality.

The Vedas are known as the revealed Truths. Vedas are the recordings of the revelations received through transcendental experiences of the Rishis of ancient India. 

Vedic knowledge is complete because it is above all doubts and mistakes, and Bhagavad-gita is the essence of all such Vedic knowledge. Out of many standard and authoritative revealed scriptures, the Bhagavad-gita is the best. The Bhagavad-gita however is a part of the epic Mahabharata.

The humans are divided by vedas according to their orders of life namely Brahmacharya, Grihasthashram, Vanaprastha and Sanyasa and vedas teach us how a soul could be purified. To simplify the process and make them more easily performable, Maharshi Vyasa divided the Vedas into four, Rig, Yajur, Sama and Atharva in order to expand them among men.

1. Rig-Veda 
The Rig-Veda Samhita is the grandest and oldest book of the Hindus. Its immortal mantras embody the greatest truths of existence and its priest is called the Hotri. The Rig-veda contains 10,552 verses divided into 64 chapters. Besides that it has got twenty-five branches written by several Rishis. The Rig-veda contains the most sacred Gayatri mantra.

2. Yajur-Veda  
Its name is derived from the root word 'yaj' meaning worship. The term for sacrifice i.e. yajna is also derived from here. It primarily deals with the procedural details for performing different yajnas

There are two distinct Yajur Veda Samhitas, the Shukla Yajur Veda or Vajasaneyi Samhita and the Krishna Yajur Veda or Taittireya Samhita. The Krishna or the Taittireya is the older book and the Sukla or the Vajasaneyi is a later revelation to sage Yajnavalkya from the resplendent Sun God. About half of the Yajur-Veda are composed of verses taken from the Rig-Veda. They are arranged according to their importance in various rituals. The remaining part (mainly prose) deals with the formulae for performing the yajna, external as well as internal. The famous Rudra hymns belong to the Krishna Yajur Veda. The Yajur-Veda contains 1875 verses. Besides that it has got one hundred and eight branches.

3. Sama-Veda      
The Sama-Veda Samhita is mostly borrowed from the Rig-vedic Samhita, and is meant to be sung by the Udgatri, the Sama-vedic priest, in sacrifices. 'Sama' means peace. Accordingly this Veda contains chants to bring peace to the mind. Many of the hymns of the Rig-Veda are set to musical notes in Sama Veda. Sama Veda is the basis of the seven notes (Sapta Swaras), fundamental to Indian classical music. The listening of the musical chants gives one a sense of universality and a mingling with the divine. The 'udgaata' or beginning ceremony before a yajna is actually a chanting of hymns from Sama Veda to ensure the grace of all the Devas. The Sama-Veda contains approximately 2000 verses. Besides that it has got one thousand branches.

4. Atharva-Veda 
This Veda is named after a sage called Atharvan who discovered the mantras contained in it. It is basically a book of magic spells to ward off evil and suffering and to destroy one's enemies. It deals more with the things here and now, than the hereafter, and with the sacrifices which are a means to them. The mantras are in prose as well as verse. There also hymns addressed to devas other than the ones mentioned in the other three Vedas. There are hymns, which deal with creation also. Brahma is the representative of Atharva Veda. The Atharva Veda gives a useful insight into the rich landscape of India at the time of its composition.
The Atharva Veda contains of 5987 verses. Besides that it has got fifty branches.
Yajur-veda and Sama-veda use the hymns of Rig-Veda and Atharva-Veda and rearrange them in a manner suitable for rituals.

In all, the four Vedas have got One thousand one hundred and eighty three (1183) branches. Each Veda consists of four parts to suit the four stages in a man's life- Brahmacharya, Grihasta, Vanaprastha and Sanyasa. The four divisions are Mantra Samhitas, Brahmanas, Aranyakas and Upanishads.

The Mantra-Samhitas which are hymns in praise of the Vedic God for acquiring material prosperity and happiness. They are poems comprising prayers, hymns and incantations addressed to various deities. This portion also contains information about the creative process, the universal laws, about the creation and the universe in detail. It is useful to Brahmacharins.

II. BRAHMANAS
The Brahmanas are explanations of Mantras or rituals, which give guidance to people as to how; the sacrificial rites are to be performed. They are explanations of the method of using the Mantras in Yajnas or other rites. Details for various ceremonies like birth, naming, study, marriage, death are in this portion. The Brahmana portion is suitable for householders (Grihastashram).

Brahmanas of Rig-veda
There are three Rig-vedic Brahmanas.
1. Ithareya Brahmana
2. Sankhayana Brahmana
3. Kausheethaki Brahmana

Brahmanas of Yajur-veda
There are three Yajur-vedic Brahmanas.
1. Shatapadha Brahmana
2. Thaiththareeya Brahmana
3. Maithrayaneeya Brahmana

Brahmanas of  Sama-veda
There are  nine Sama-vedic Brahmanas.
1. Jaimineeya Brahmana
2. Thandya Brahmana
3. Aarsheya Brahmana
4. Shadvimsadhi Brahmana
5. Chandhokya Brahmana
6. Samavidhana Brahmana
7. Abhootha Brahmana
8. Vamsa Brahmana
9. Samhithopanishathi Brahmana

Brahmanas of Atharva-veda
1. Gopadha Brahmana

III.  ARANYAKAS
The Aranyakas are the forest books, the texts that give philosophical interpretations of the rituals. After a man has finished all his worldly duties ( taking care of parents, marrying off children etc.) he proceeds to the forest to spend the rest of his days in solitude and meditation. The Aranyakas are intended for such people, hence the name. It explains the different kinds of rituals to be performed in forest by people, who go for Vanaprastha.

The Aranyakas are expositions on the inner meaning of the Vedic hymns and sacrifices. The hymns are interpreted symbolically to gain an insight into the reasons for performing yajnas and thus deal with higher metaphysical concepts.

Aranyakas of Rig-veda
There are two  Rig-vedic Aranyakas.
1 Ithareya Aranyaka
2 Kausheethaki Aranyaka

Aranyakas of Yajur-veda
There are two Yajur-vedic Aranyakas.
1 Maithrayaneeya Aranyaka
2 Thaiththareeya Aranyaka

There is no Aranyakas for Sama and Atharva vedas.

IV. UPANISHADS
The Upanishads are the essence of Vedic teaching. They are called Vedantas meaning the concluding portion of the Vedas as well as the ultimate conclusions of Vedic wisdom. Upanishads happen to be the most foremost authorities of the Vedanta system of philosophy that developed in later times in different forms.
 
They reveal the most subtle and deep spiritual truths and are meant for Sanyasins. The collection of teachings generated by the ascetics who meditated on the mysteries of human existence came to be known as the Upanishads, which literally means "sitting close to" the teacher thereby indicating that the knowledge that it imparts is esoteric. Many, many Upanishads existed ages ago; a lot of them have been lost in the dark backward abysm of time. Only one hundred and eight have been preserved so far some in prose, some in verse. They are:

Upanishads of Rig-Veda
There are ten Rig-vedic Upanishads. They are
1 Ithareya Upanishad
2 Kausheethaki Upanishad
3 Nadhabindhu Upanishad
4 Aathmabhodha Upanishad
5 Nirvana Upanishad
6 Mulgala Upanishad
7 Akshamalika Upanishad
8 Tripura Upanishad
9 Sowbhagyalakshmi Upanishad
10 Bhahvrucha Upanishad

Upanishads of  Sukla Yajur-veda
There are eighteen Sukla Yajur-vedic Upanishads. They are
1 Isovaasya Upanishad
2 Bruhadharanyaka Upanishad
3 Hamsa Upanishad
4 Paramahamsa Upanishad
5 Subhala Upanishad
6 Mantrika Upanishad
7 Thrisikibrahmana Upanishad
8 Niralamba Upanishad
9 Mandalabrahmana Upanishad
10 Adhwya Upanishad
11 Taraka Upanishad
12 Bhikshuka Upanishad
13 Adhyaatma Upanishad
14 Muktika Upanishad
15 Tarashara Upanishad
16 Yanjavalkya Upanishad
17 Shatyayana Upanishad
18 Turiyatheeya  Avadhootha Upanishad

Upanishads of Krishna Yajur-veda
There are thirty two Krishna Yajur-vedic Upanishads. They are
1 Kada Upanishad
2 Thaiththireeya Upanishad
3 Brahma Upanishad
4 Kaivalya Upanishad
5 Swetaswetara Upanishad
6 Garbha Upanishad
7 Mahanarayana Upanishad
8 Amrithabindhu Upanishad
9 Amrithanadha Upanishad
10 Kalagnirudra Upanishad
11 Kshurika Upanishad
12 Sarvasara Upanishad
13 Shukarahasya Upanishad
14 Tejabindhu Upanishad
15 Dhyanabindhu Upanishad
16 Brahmavidhya Upanishad
17 Yogatatva Upanishad
18 Dhakshinamoorthy Upanishad
19 Skanda Upanishad
20 Saareerika Upanishad
21 Yogashika Upanishad
22 Ekakshara Upanishad
23 Akshi Upanishad
24 Avadhootha Upanishad
25 Kadarudra Upanishad
26 Rudrahrudhaya Upanishad
27 Panchabrahma Upanishad
28 Pranagnihotra Upanishad
29 Varaha Upanishad
30 Yogakundalini Upanishad
31 Kalisantarana Upanishad
32 Saraswatheerahasya Upanishad

Upanishads of  Sama-veda
There are sixteen Sama-vedic Upanishads. They are
1 Kena Upanishad
2 Chandokya Upanishad
3 Aaruni Upanishad
4 Maitrayanee Upanishad
5 Maitreyee Upanishad
6 Vajrasuchika Upanishad
7 Yogachoodamani Upanishad
8 Vasudeva Upanishad
9 Maha Upanishad
10 Sanyasa Upanishad
11 Avyakta Upanishad
12 Kundika Upanishad
13 Savitri Upanishad
14 Jabhala Upanishad
15 Darsana Upanishad
16 Rudraksha Jabhala Upanishad

Upanishads of  Atharva-veda
There are thirty two Atharva-vedic Upanishads.They are
1 Prasna Upanishad
2. Mundaka Upanishad
3. Maandukya Upanishad
4. Atharvasira Upanishad
5. Atharvasikha Upanishad
6. Bruhat Jaabhala Upanishad
7. Sita Upanishad
8. Sarabha Upanishad
9. Mahanarayana Upanishad
10. Ramarahasya Upanishad
11. Ramatapini Upanishad
12. Sandilya Upanishad
13. Paramahamsa Upanishad
14. Annapoorna Upanishad
15. Surya Upanishad
16. Aathma Upanishad
17. Pasuptha Upanishad
18. Parabrahma Upanishad
19. Tripuratapini Upanishad
20. Devi Upanishad
21. Bhavana Upanishad
22. Bhasma Jaabhala Upanishad
23. Ganapati Upanishad
24. Mahakavya Upanishad
25. Gopalatapini Upanishad
26. Sreekrishna Upanishad
27. Hayagriva Upanishad
28. Dhaththathreya Upanishad
29. Garuda Upanishad
30. Narasimhapurvatapini Upanishad
31. Naradapariprajaka Upanishad
32. Narasimha Uththaratapini Upanishad

Besides this 108 Upanishads, so many Upa-Upanishads are also there.

V. VEDANGAS
The Vedangas and Upavedas are collections of texts that augment and apply the Vedas as a comprehensive system of sacred living. There are six Vedangas.

1. Siksha (The nose of the Vedas)
Siksha means Vedic phonetics and lays down the rules of phonetics - sounds of syllables, of pronunciation- euphony. It lays down the parameters of Vedic words. Phonetics are very important in Vedic language because a slight change in sound may lead to change in the meaning of a mantra and consequently have undesirable effects on the sacrifice. Siksha explains how the sound of each syllable should be produced, how high or low should be its pitch and for how much duration (maatra) the sound must last.

2. Nirukta (The ears of the Vedas)
Nirukta is the Vedic dictionary. Nirukta may be regarded as the Vedic equivalent of etymology i.e. the study of words. Nirukta explains the origin of each Sanskrit word in the Vedas. In Sanskrit, names or words are not assigned ad-hoc but there is a systematic way of forming words. Every word has a deep meaning and may sometimes be formed by the combination of two or more nouns. All words are derived from the basic roots or Dhatus. As Nirukta breaks each word into its component roots and analyses its meaning, so it is likened to the ear, which distinguishes speech by breaking words into its component phonemes. It is also regarded as the World’s first Encyclopedia.
 
3. Vyakarana (The mouth of the Vedas.)
Vyakarana deals with grammar and so is very important. There are many books on Sanskrit grammar, but the most famous and most extensively used is the Vyakarna of Sage Paanini. Paanini's grammar is in the form of aphorisms (Sutras).

4. Chanda Saastra (The feet of the Vedas)
Chanda Saastra deals with metric composition. Any verse has to have a specified 'metre' and number of letters in it, for a good fit. Chanda Saastra lays down the rules for this. It defines the boundaries of metrical composition into metre, rhyme, etc. 

5. Kalpa Saastra (The arms of the Vedas)
Kalpa Saastra is a collection of books of Shauwta Sutra, Dharma Sutra, Pithrumedha Sutra, Sulba Sutra, Gruhya Sutra and Prayaschitham. All our customs and rituals are explained in Kalpa saastra.

Kalpa Saastra answers the questions like:

How should a ritual be performed?
What are the duties of the child, student, householder, King, mendicant etc?
Which ritual involves which mantra, which material and which Deva?
How many priests should be employed for a sacrifice?
What objects should be used in various rituals?, and so on.
 
The Kalpa Saastra details the Vedic rituals to be performed from the time the embryo forms in the womb to birth leading upto the final sacrifice of death. Cremation or Antiyeshti, meaning the last rite is seen as a sacrifice of the whole body to Agni, the fire god. The Namakarana (naming ceremony), the Upanayana (sacred thread investiture ceremony), Vivaaha (marriage) are also described within the Kalpa. The Vedic system of architecture i.e. Vaastu Shastra is also described in Kalpa. The entire Kalpa Saastra weighs more than 250 Kilograms. (i.e., 2.5 quintals)

6. Jyothisha (Astronomy + Astrology) The eyes of the Vedas
Jyothisha includes Ganitham, Kalakriya, Golam, Jatakam, Muhurtham, Prasnam and Nimiththam.
Perhaps the most famous of all Vedangas, it is the science of astrology. Jyotisha gives rules to calculate the positions of the planets and stars at any instant in the future or past. Based on these positions and certain well defined rules, the fate of a person can be reasonably determined provided his/her birthdate, time and place of birth are accurately known. Vedic astrology is based on lunar signs in direct contrast to the solar sign system prevalent in the west. The premise is that the moon being closer to the Earth extends a greater influence on mankind than the distant Sun.

VI. UPAVEDAS
There are five Upavedas
1. Arththasaastra
      Unfolds statecraft. It can be called as the Hindu science of governing by Kings.
2. Dhanur Veda
      Discusses military science. Discusses different kinds of weapons and war rules.
3. Gandharva Veda
The science which enlighten music and arts. Discusses different kinds of music, musical instruments and arts.
4. Ayurveda
      Deals with medicine, health and longevity.
5. Saapadhyaveda ( Tachchu Saastra )
      Deals with the architecture. Vasthu Saastra also comes under this.

VII.  PURANAS
Puranas are compiled from related historical facts, which explain the teachings of the four Vedas. The Puranas explain the Vedic truths and are intended for different types of men. All men are not equal. There are men who are good, others who are driven by passion and others who are under the veil of ignorance. The Puranas are so divided that any class of men can take advantage of them and gradually regain their original nature and get out of the hard struggle for existence

Mahapuranas
There are eighteen Mahapuranas. They are
1. Vishnu Purana
2. Bhavishya Purana
3. Garuda Purana
4. Agni Purana
5. Mahabhagavata Purana
6. Siva Purana
7. Markandeya Purana
8. Linga Purana
9. Brahmavaivarththa Purana
10. Matsya Purana
11. Kurma Purana
12. Varaha Purana
13. Vamana Purana
14. Skanda Purana
15. Brahmaanda Purana
16. Patma Purana
17. Vayu Purana
18. Naradheeya Purana

Upa-puranas
There are eighteen Upa-puranas. They are
1. Samba Purana
2. Devibhagavata Purana
3. Kalika Purana
4. Lakhunaradheeya Purana
5. Harivamsa Purana
6. Vishnudharmmoththara Purana
7. Kalki Purana
8. Mulgala Purana
9. Aadhi Purana
10. Aathma Purana
11. Brahma Purana
12. Vishnudharma Purana
13. Narasimha Purana
14. Kriyaayoga Purana
15. Surya Purana
16. Bruhat Naradheeya Purana
17. Prushoththama Purana
18. Bruhat Vishnu Purana

VIII. DARSANAS
Darsana means, sight or vision. In the Vedanta philosophy, the first question is what is the source of everything? There are philosophers who saw different stages of the original source, and explained philosophy according to their vision. These are known as Darsanas. They are also known as Sad-darsanas (six systems of philosophy).

1. Nyaya Darsana 
Nyaya means the science of logic and expediency. It is also known as Tarka Shastra. This was composed by Sage Gautama and contains passages, which establish by means of disputation that God is the creator of this universe. It establishes the existence of God by means of inference.

2. Vaiseshika Darsana 
Vaisesika, philosophy of specialised logic, maintains that the combination of atoms is the cause of the cosmic manifestation. It was composed by Maharshi Kanada He was the first philosopher who formulated ideas about the atom in a systematic manner.

Nyaya and Vaiseshika deal mainly with physics, chemistry and other material sciences and include reasoning or logic. Metaphysical studies or search for knowledge of God, however, formed the ultimate aim of the study of these saastras also.

3. Sankhya Darsana 
Sankhya, philosophy of analytical study, maintains that the material nature is the cause of the cosmic manifestation. Sage Kapila composed it.

4. Yoga Darsana 
Yoga, philosophy of mystic perfections, maintains that universal consciousness is the cause of the cosmic manifestation. It was composed by Padanjali Maharshi. He is the first systematiser of the Yoga school. 

5. Purva Meemamsa Darsana 
Sage Jaimini composed the sutras for the Purvameemamsa, philosophy of actions and reactions, maintains that fruitive activities are the cause of the cosmic manifestation. This book consists of 12 chapters - 1000 Adhikaranas in all. In these Adhikaranas, selected Vedic verses are examined in details. In the 1000 Adhikaranas a thousand types of problems are taken up and various arguments against an apparent explanation are raised before coming to a conclusion.

6. Uththara Meemamsa Darsana
The Uttarameemamsa deals with Vedanta and is thus close to the philosophy of the Upanishads. Maharshi Veda Vyasa composed Uththara Meemamsa.

IX. SMRITIS
Smriti means memory and are writings devised to fix in memory, the practical use of the messages stated or implied in the Vedas. ‘Smritis ' embodies the teachings of Divine Incarnations or prophets, saints and sages. It is an explanation of the 'Srutis' ' Srutis ' are the revealed scriptures, as mentioned in the Vedas and ' Smritis ' are the commentaries and derived literatures, based on the messages of the Vedas;  Some of the Smritis are in the form of Laws formulated by saints and sages for mankind. There are eighteen important Smritis.They are

1. Usana Smriti
2. Yanjavalkya Smriti
3. Vishnu Smriti
4. Manu Smriti
5. Angeerasa Smriti
6. Yama Smriti
7. Atri Smriti
8. Samvarththa Smriti
9. Bruhatparasara Smriti
10. Bruhaspati Smriti
11. Daksha Smriti
12. Saataatapa Smriti
13. Likhita Smriti
14. Vyasa Smriti
15. Parasara Smriti
16. Sanka Smriti
17. Gautama Smriti
18. Vasishta Smriti

X.  ITIHASAS
Itihasas are literatures describing historical events pertaining to either a single hero or a few heroic personalities in a lineage: for example, Ramayana describing the pastimes of Sri Ramachandra and Mahabharata describing the pastimes of the Pandavas in the lineage of the Kurus. In these books there are topics on transcendental subjects along with material topics. The whole idea of the Mahabharata culminates in the ultimate instructions of the Bhagavad-gita that one should give up all other engagements and should engage oneself solely and fully in surrendering unto the lotus feet of Krishna. The conclusive teaching of the Ramayana also is to fully surrender and take shelter of Lord Sri Ramachandra.

1. Ramayana
The traditional author of this Epic is the sage Valmiki. This Epic is regarded as the first poetical work in the world, of purely human origin. The verses have great diffusivity, simplicity and charm. There are totally seven books of this great epic.

2. Mahabharata
This epic is traditionally authored by the sage Vyasa It is a rich collection of many histories and legends. The scene of the poem is the ancient kingdom of the Kurus; and the central story - ' the germ of which is to be found in the Vedas ' - concerns a great dynastic war. A very important portion of the Mahabharata is the Song of the God (called the Gita). Bhagavad Gita, as it is called, is the essence of all the messages to mankind contained in the Veda.

Acknowledgement.
Dr.N.GopalaKrishnan,Scientist, CSIR & Hon Director, Indian Institute of Scientific Heritage, Trivandrum, ph 0471- 490149.

Thus the primary texts of Sanathana Dharma includes four Vedas, Sixteen Brahmanas, four Aranyakas, One Hundred and Eight  Upanishads,  Six  Vedangas, five Upavedas, eighteen  Mahapuranas, eighteen  Upapuranas, six Darsanas, eighteen Smritis and two Ithihasas.

While other religions got only one book, Sanathana Dharma or Hindu Dharma has got huge amounts of books. Please forward this document to everyone you know. Remember, it is your, mine and our duty, privilege and responsibility to learn, teach and spread our Heritage.