Veda Vargeekarana (वेदवर्गीकरणम्)

Veda (Samskrit : वेदः) is regarded as revealed scripture, self-explanatory and self authoritative, according to many traditional Indian scholars. वैदिकसूक्त-s || Vedic Suktas (Collection of Mantras) and मन्त्र-s || Mantras are "seen by" or "revealed to" and only spoken by the ऋषि-s || Rishis (seers or sages). These rishis are neither authors of the Mantras nor are they responsible for the contents of the Mantras. Thus, Vedas are called अपौरुषेयः ॥ Apaurusheya. There is no final authority beyond the Vedas according to Bharatiya philosophy. While the mantras are revealed, the structural arrangement of Vedas given by वेदव्यासः ॥ Veda Vyasa and further formation of शाखा-s || shakas (recensions) or versions of Vedas seen today is based on different rishis.

परिचयः || Introduction

महर्षिः वेदव्यासः || Maharshi Veda Vyasa collected all the Mantras in existence during his period, edited, codified and organized them into four groups in the form that we see today.

1. ऋग्वेदः || The Rigveda
2. यजुर्वेदः || The Yajurveda
3. सामवेदः || The Samaveda
4. अथर्वणवेदः || The Atharvanaveda

Of these, the first three were the principal original division, also called त्रयी-विद्या || Trayi vidya, that is, 'the triple science' of reciting mantras (Rigveda), performing यज्ञ-s ॥ yajnas (sacrifices) (Yajurveda), and singing of mantras set to musical notes (Samaveda). Atharvaveda consists of mantras applicable to activities of daily life, such as ailments and their cure, achieving desired things, warfare, trade, commerce, construction among other things.    

ऋग्वेदः || Rigveda

व्युत्पत्तिः ॥ Etymology

The Samskrit धातुः "ऋच्" (तुदादि-गणः) is used in the meaning स्तुतिः || Stuti (to praise). That which has the description of the quality, action and nature of substances is said to be ऋक् (Rk). Variously called as 'rk or rik (ऋक्)', 'richas (ऋचाः)', 'rig (ऋग्)', these Mantras are meant for the praise of the deities.

Rigveda contains primarily Mantras (set in 2, 3 or 4 पादा-s || padas) dealing with the stuti for devatas, their invocation, yajnakarmas, कर्मकाण्डः ॥ karmakanda, उपासना-मन्त्राः ॥ upasana mantras, mantras related to different worldly activities such as दानम् ॥ dana, conduct, medical remedies etc.

ऋग्वेद-विभाजनम् ॥ Rigveda Vibhajana

There are two types of divisions of Rigveda namely, मण्डल-क्रमः ॥ Mandala krama and अष्टक-क्रमः ॥ Ashtaka krama. They arose mainly for अध्ययनम् || study and अध्यापनम् || teaching. A small lesson is easily grasped or understood and committed to memory.(See footnote 3 on Page 35 of Reference 1) There are different versions advocated by different scholars about the number of सूक्त-s || suktas and मन्त्र-s || mantras available in Rigveda.

मण्डल-क्रमः ॥ Mandala Krama

This division of the Rigveda is most popular and systematic. According to the मण्डल-क्रमः ॥ Mandala krama, ऋग्वेद-संहिता ॥ Rigveda Samhita is divided into 10 Mandalas or books. The Mandalas are subdivided into 85 अनुवाक-s || Anuvakas, 1028 सूक्त-s || Suktas and 10522 मन्त्राः ॥ mantras and 10552 mantras according to another version. In Rig veda, in शाकल-संहिता ॥ Shakala samhita, the number of suktas in each Mandala is - 191, 43, 62, 58, 87, 75, 104, 103, 114, 191 (1028) respectively from the first to tenth Mandala.

मण्डलम् ॥ Mandala      ►	अनुवाकः ॥ Anuvaka      ►	सूक्तम् ॥ Sukta       ►	मन्त्रः ॥ Mantra

Thus the structure is as follows

• Each Mandala is divided into several sections called Anuvakas.
• Each Anuvaka consists of a number of Suktas (hymns).
• Each Sukta is made up of a number of Mantras (verses) called rks. 

Rigveda contains 10552 mantras (about 10,170 Rks) according to some other scholars, spread over 1028 Suktas and 85 Anuvakas in 10 Mandalas. According to शौनक-ऋषिः ॥ Shaunaka rishi there are 10580 mantras (Page 17 of Reference 4).

In Rigveda, not only are the suktas and mantras counted but a system of counting even the Aksharas (अक्षर-s | letters) exists given in texts called as Sarvanukramanis (सर्वानुक्रमणी). Such system leaves no scope of additions or deletion of letters in the Veda. This was the main reason why the Vedic text has not undergone any change since ancient times.

The differences in the counting of mantras is mainly because of the differences in the शाखाः ॥ shakhas. Additionally in modern times the differences in counting the ऋक्-s || Rks is attributed to breaking the mantras having 4 padas (पादा-s) into 2 padas each (Page No 6 of Reference 4).

वालखिल्य or खिलसूक्ताः || Valakhilya or Khila Suktas

According to शौनक-अनुक्रमणिका ॥ Shaunaka Anukramanika, 11 suktas of वालखिल्य-s || Valakhilyas are present. Removing which from the total number of suktas (1028), will yield 1017 Suktas in Rigveda Samhita. वष्कल ॥ Vashkala or बाष्कल-शाखा ॥ Bashkala shakha has 8 suktas more than 1017. Thereby it is mentioned as having 1025 Suktas.

'Khila' is defined as the Appendix (those which are appended in the end). They are included in the vedic study practice (स्वाध्याय) but lack the Padapatha (पदापाठः) and excluded in Aksharaganana (अक्षरगणना | counting of Aksharas) thus their exact nature is unclear. The location of Khila Suktas is clear in Mandala krama, starting from Suktas 49 to 59 including 80 mantras in the 8th Mandala.

अष्टक-क्रमः ॥ Ashtaka Krama

According to the अष्टक-क्रमः ॥ Ashtaka krama, ऋग्वेद-संहिता ॥ Rigveda Samhita is divided into 8 अष्टक-s || Ashtakas each containing 8 अध्याय-s || Adhyayas. Thus, a total of 64 Adhyayas are available. The number of वर्ग-s || Vargas in each Ashtaka is - 265, 221, 225, 250, 238, 331, 248, 246 respectively from first to eighth Ashtaka. Thus, a total of 2024 वर्गाः ॥ vargas are present in ऋक्-संहिता ॥ Rk samhita. The total number of mantras are 10522 according to some scholars(Page 34 of Ref 1).

अष्टकः ॥ Ashtaka      ►	अध्यायः ॥ Adhyaya      ►	वर्गः ॥ Varga       ►	मन्त्रः ॥ Mantra

Thus the structure is as follows

• Each Ashtaka is divided into several sections called Adhyayas.
• Each Adhyaya consists of a number of Vargas.
• Each Varga is made up of a number of Mantras (rks). 

The ashtaka system of dividing the contents of the Rigveda, is uncommon among the students of the Veda.

शाखाः ॥ Shakhas

Only one Shaka (school or recension) of the Rigveda is available today

• शाकल-शाखा || Shakala shakha

Presently Shakala (शाकल), Bashkala (बाष्कल), Shankhyayana (शाङ्ख्यायन), Mandukayana (माण्डूकायन) and Ashvalayana (अश्वलायन) shakas of Rig veda though are said to be available shakas, apart from Shakala shaka, the Samhita part of other four shakas are unavailable.

According to सर्वानुक्रमणि-वृत्तिः ॥ Sarvanukramani vritti, अहिर्बुध्न्यसंहिता ॥ Ahirbudhnyasamhita, मुक्तिकोपनिषद् ॥ Muktikopanishad and पतञ्जलेः महाभाष्यम् ॥ Patanjali's Mahabhashya, and recently many scholars opined that Rigveda had 21 shakhas.

However, according to Pt. Satyavrat Samashrami, Rig veda has only 2 ancient shakhas namely, शाकलः || Shakala and माण्डूकेयः || Mandukeya. These two shakhas became 21 shakhas gradually. शाकलाचार्यः ॥ Shakalacharya taught this veda to 5 of his disciples and gradually in their pronunciation there were differences bringing about 5 different versions of the Veda, which according to the text विकृति-कौमुदी ॥ Vikruti Kaumudi is as follows:

शाकल्यसेय शतं शिष्या नैष्ठिकब्रह्मचारिणः | पञ्च तेषां गृहस्थास्ते धर्मनिष्ठाश्च कुटुम्बिनः ||

शिशिरो वाष्कलो सांख्यो वात्स्यश्चैवाश्वलायनः | पञ्चैते शाकलाः शिष्याः शाखाभेदप्रवर्त्तकाः ||

śākalyaseya śataṃ śiṣyā naiṣṭhikabrahmacāriṇaḥ | pañca teṣāṃ gṛhasthāste dharmaniṣṭhāśca kuṭumbinaḥ ||

śiśiro vāṣkalo sāṃkhyo vātsyaścaivāśvalāyanaḥ | pañcaite śākalāḥ śiṣyāḥ śākhābhedapravarttakāḥ ||

Meaning : शाकलः ॥ Shakala had 100 students who were brahmacharis. Of them, 5 who were having धर्मनिष्ठा ॥ dharmanishtha were grhasthas bearing the responsibility of maintaining a family. शिशिरः || Shishira, वाष्कलः || Vashkala (Bashkala), शाङ्ख्यः || Sankhya, वात्स्यः || Vatsya and अश्वलायनः || Ashvalayana were the five disciples who were the प्रवर्तक-s || pravartakas of the different shakhas. Ashvalayana Samhita was available as lately as 17th century but is presently unavailable. शाङ्खायन-संहिता ॥ Sankhayana samhita is not available but its Brahmanas and Aranyakas are available. Some scholars opine that शाङ्खायन ॥ Sankhayana and कौषीतकी शाखाः॥ Kaushitaki shakhas are one and the same.

विषयविभागाः ॥ Vishayavibhaga

The topics dealt with in the ऋग्वेद-संहिता ॥ Rigveda Samhita can be classified into 3 groups.

• स्तुतिपराः || Eulogical : Praise and prayers to the deities like Agni, lndra, Varuna, Mitra and others.
• उपासनापराः ॥ Philosophical : Rudimentary form of vedanta is seen, with philosophical speculations like the origin of the Universe and the real nature of human beings.
• इतिहासपराः ॥ Miscellaneous : Subjects like marriage, war etc., which depict the nature of society of those times are described.

ब्राह्मणानि आरण्यकानि उपनिषदः च ॥ Brahmanas, Aranyakas and Upanishads

• ऐतरेय-ब्रह्मणं कौषीतकी ब्राह्मणमं च ॥ Aitareya and Kausitaki Brahmanas
• ऐतरेय-आरण्यकं शाङ्खायन-आरण्यकं च ॥ Aitareya and Sankhyayana Aranyakas
• ऐतरेय-उपनिषद् ॥ Aitareya Upanishad

यजुर्वेदः || Yajurveda

व्युत्पत्तिः ॥ Etymology

According to शब्दकल्पद्रुमः ॥ Shabdakalpadruma,

इज्यतेऽनेनेति यजुः || ijyate'neneti yajuḥ ||

Meaning: performance of yajnas using this (mantra) hence called यजुस् ॥ Yajus.

अनियताक्षरावसानो यजुः ॥ aniyatākṣarāvasāno yajuḥ ॥

Meaning: that which has no regulation (metrical) of letters is called Yajus. According to Pt Gajanan Shastri - the word yajus is derived by the combination of यज् || yaj and उसि || usi.

गद्यात्मको यजुः || gadyātmako yajuḥ ||

Meaning: Yajus are (the mantras) in prose form.

Following texts clearly define the purpose of "Yajus" mantras in yajnas and hence the name Yajurveda is given.

• निरुक्तम् ॥ Nirukta, यजुः यजतेः । ७.१२ ।yajuḥ yajateḥ । 7.12 । यज्ञ-s || Yajnas are conducted with यजुस् ॥ Yajus (mantras).

• कठसंहिता ॥ Katha Samhita (27.1), यजर्भियजन्ति ॥ yajarbhiyajanti and (Kath. Samh. 200.21) यजुस्तस्माद् (यज्ञात्) अजायत ॥ yajustasmād (yajñāt) ajāyata

• ब्रह्माण्डपुराणम् ॥ Brahmanda Purana : यच्छिष्टं तु यजुर्वेदे तेन यज्ञमयुंजत । यजनात्स यजुर्वेद इति शास्त्रविनिश्चयः ।। ३४.२२ ।। yacchiṣṭaṃ tu yajurvede tena yajñamayuṃjata । yajanātsa yajurveda iti śāstraviniścayaḥ ।। 34.22 ।। (Brah. Pura. Purvabhaga 34.22)

यजुर्वेद-विभजनम् ॥ Yajurveda Vibhajana

The divisions of the text for शुक्लयजुर्वेदः ॥ Shukla Yajurveda are slightly different and include a combination of these as given below (See Page xix of the Introduction in Reference ). However, variations of these divisions is seen according to other scholars.

काण्डः ॥ Kanda      ►	अध्यायः ॥ Adhyaya ►	प्रपाठकः ॥ Prapathaka ►	ब्राह्मणम् ॥ Brahmana ►	काण्डिका ॥ Kandika

• माध्यन्दिन-शाखा ॥ Madhyandina Shakha : 40 अध्यायाः ॥ Adhyayas and 1975 मन्त्राः ॥ mantras, 90525 अक्षराणि ॥ aksharas.
• काण्व-संहिता ॥ Kanva Shaka : 40 अध्यायाः ॥ Adhyayas and 2086 मन्त्राः ॥ mantras.

The divisions of the text for कृष्ण-यजुर्वेदः ॥ Krishna Yajurveda have different arrangements. Following are the textual divisions in तैत्तिरीय-शाखा ॥ Taittriya shakha which is representative of Krishna Yajurveda.

काण्डः ॥ Kanda      ►	प्रपाठकः ॥ Prapathaka ►	अनुवाकः ॥ Anuvaka ►	मन्त्रः वा काण्डिका ॥ Mantra or Kandika

In some south Indian parts where this shakha is widely followed, there are other terms such as Panasa and प्रश्नः ॥ Prashna (ex: रुद्रप्रश्नः ॥ Rudraprasha) are in usage. सारस्वत् ॥Saraswat and आर्षेय ॥ Arsheya system of classification are also seen for Krishna Yajurveda.

• तैत्तिरीय-शाखा ॥ Taittriya Shakha - 7 काण्डाः ॥ kandas, 44 प्रपाठकाः ॥ Prapathakas, 651 अनुवाकाः ॥ Anuvakas (631 according to Page 9 of Reference ), 2198 काण्डिकाः ॥ Kandikas are present.
• मैत्रायणी शाखा ॥ Maitrayani Shaka - 4 काण्डाः ॥ kandas, 11 प्रपाठकाः ॥ Prapatakas, 3144 मन्त्राः ॥ mantras.
• कठ-संहिता ॥ Kathasamhita - 40 अध्यायाः ॥ Adhyayas, 843 अनुवाकाः ॥ Anuvakas, 3091 मन्त्राः ॥ mantras.
• कपिष्ठल-संहिता ॥ Kapisthalakatha - 6 अष्टकाः ॥ Astakas, 48 अध्यायाः ॥ Adhyayas.

Thus, as seen above, different classification systems are seen for every शाखा ॥ shakha.

शाखाः ॥ Shakhas

The number of यजुर्वेदशाख-s ॥ Yajurveda shakhas is given variously by different ऋषि-s || rishis and scholars as

• 101 shakhas (recensions)
• 101 out of which 86 were कृष्णयजुर्वेदः ॥ Krishna Yajurveda and 15 belonged to शुक्लयजुर्वेदः ॥ Shukla Yajurveda
• 107 according to सूतसंहिता ॥ Sutasamhita, स्कन्दपुराणम् ॥ Skanda Purana and ब्रह्माण्डपुराणम् ॥ Brahmanda Puranas
• 109 according to मुक्तिकोपनिषद् ॥ Muktikopanishad
• 100 according to पतञ्जलिः ॥ Pathanjali in his महाभाष्यम् ॥ Mahabhasya
• 86 according to चरणव्यूहम् ॥ Charanavyuha and शौनकः ॥ Shaunaka.
• According to वायु-पुराणम् ॥ Vayu Purana, there were 86 student lineages and thus, 86 शाखाः ॥ shakhas of महर्षिः वैशम्पायनः ॥ Maharshi Vaisampayana are mentioned.
• विष्णुपुराणम् ॥ Vishnupurana and अग्निपुराणम् ॥ Agnipurana give a number of 27 शाखाः ॥ shakhas of यजुर्वेदः || Yajurveda.

Thus, quite some variation is seen in the number of shakhas that existed for Yajurveda.

In the present day, five Shakas of Yajurveda are seen namely तैत्तिरीय ॥ Taittriya, कठ ॥ Katha or कपिष्ठल ॥ Kapisthala, मैत्रायणी ॥ Maitrayani, वाजसनेयी ॥ Vajasaneyi and काण्व ॥ Kanva according to some scholars.

Many scholars view the classification into two major groups or शाखा-s || Shakhas :

• कृष्ण-यजुर्वेदः ॥ Krishna Yajurveda
• शुक्ल-यजुर्वेदः ॥ Shukla Yajurveda

Today, a vast majority of people follow the Yajurveda. Krishna Yajurveda is common in the South of India and Shukla Yajurveda in the North.

Shukla Yajurveda Shakhas (15) : Charanavyuha book mentions the 15 Shukla Yajurveda shakas as follows :

Kanva, Madhyandhina, Shopeyaha, Tapayaneeyaha, Kapalaha, Poundravastasha, Avatikaha, Paramavatikaha, Parasharyaha, Vaidheyaha, Vaineyaha, Audheyaha, Galavaha, Vaijavaha, Katyayaneyaha. Of these, presently, only काण्व ॥ Kanva and माध्यन्दिन-संहिता ॥ Madhyandina samhitas are available

Krishna Yajurveda Shakhas : Of the 86 shakas only four are available : तैत्तिरीय ॥ Taittiriya, कठ ॥ Katha, कपिष्ठल ॥ Kapisthala, and मैत्रायणी ॥ Maitrayani

कृष्णयजुर्वेद-संहिता || Krishna Yajurveda

The term कृष्ण || krishna of the shakha is so given due to following reasons

1. It contains both the छन्दोबद्ध ॥ Chandas (metrical) and गद्यात्मक ॥ Gadya (prose) forms of mantras
2. The texts of Mantras and ब्राह्मण-s || Brahmana (which explain the usage of the mantras) parts of the Veda are mixed.

This samhita is said to have contained 85 Shakhas but only four of them are available now, out of which the Taittiriya Samhita is widely studied and followed especially in South India and other three Shakhas are not so well known.

Texts of the four major shakhas that have survived are

1. तैत्तिरीय || Taittiriya
2. कठ/काठक || Katha or Kathaka
3. कपिष्ठल-कठ || Kapisthala-Katha
4. मैत्रायणी || Maitrayani

ब्राह्मणानि आरण्यकानि उपनिषदः च ॥ Brahmanas, Aranyakas and Upanishads

The ब्राह्मण-s ॥ Brahmanas, आरण्यक-s || Aranyakas and उपनिषद्-s || Upanishads related to this संहिता ॥ Samhita are-

1. तैत्तिरीय-ब्राह्मणम् ॥ Taittiriya Brahmana
2. तैत्तिरीय-आरण्यकम् ॥ Taittiriya Aranyaka and मैत्रायणी आरण्यकम् ॥ Maitrayani Aranyaka
3. तैत्तिरीय-उपनिषद् ॥ Taittiriya Upanishad
4. कठोपनिषद् ॥ Kathopanishad
5. श्वेताश्वतरोपनिषद् ॥ Shvetaswatara Upanishad
6. मैत्रायणी उपनिषद् ॥ Maitrayani Upanishad
7. महानारायण-उपनिषद् ॥ MahaNarayana Upanishad.

शुक्लयजुर्वेद-संहिता || Shukla Yajurveda

The term शुक्ल || Shukla of the शाखा ॥ shakha is so given due to following reasons :

1. It contains only the छन्दस् ॥ Chandas (metrical) forms of mantras without any prose content.
2. Mantras are arranged in an orderly manner.

The Shukla Yajurveda separates the Samhita from its ब्राह्मणम् ॥ Brahmana (the शतपथ-ब्राह्मणम् ॥ Shatapatha Brahmana).

This Samhita was said to contain 15 shakhas (See footnote 1 in Page 20 of Reference ) which were called वाजसनेयी ॥ Vajasaneyi. शुक्ल-यजुर्वेद-संहिता || Shukla Yajurveda Samhita is said to have been brought to the knowledge of the world by the famous sage याज्ञवल्क्यः || Yajnavalkya from Vajasani which means the सूर्य-देवता ॥ Surya devata. Hence, this is also known as वाजसनेयी संहिता || Vajasaneyi Samhita. Shatapatha Brahmana (14.9.5.33) clearly mentions that the Shukla Yajus are expounded by Yajnavalkya

आदित्यानीमानि शुक्लानि यजूंषि वाजसनेयेन याज्ञवल्क्येनाख्यायन्ते || (Shat. Brah. 14.9.5.33)

ādityānīmāni śuklāni yajūṃṣi vājasaneyena yājñavalkyenākhyāyante || (Shat. Brah. 14.9.5.33)

Meaning : From आदित्य ॥ Aditya these शुक्लयजुस् ॥ shukla yajus (मन्त्राः ॥ mantras) are given to याज्ञवल्क्यः ॥ Yajnavalkya through वाजसनेयः ॥ Vajasaneya.

Texts of only two major shakhas have survived

1. माध्यन्दिनः ॥ Madhyandina
2. काण्वः ॥ Kanva

ब्राह्मणानि आरण्यकानि उपनिषदः च ॥ Brahmanas, Aranyakas and Upanishads

The ब्राह्मण-s ॥ Brahmanas, आरण्यक-s || Aranyakas and उपनिषद्-s || Upanishads related to this संहिता ॥ Samhita are-

1. शतपथ-ब्राह्मणम् ॥ Shatapatha Brahmana. This is a work extensively serving as a general guide to all the Vedas.
2. बृहदारण्यकम् ॥ BrhadAranyaka
3. ईशावास्योपनिषद् ॥ Isavasyopanishad
4. बृहदारण्यकोपनिषद् ॥ Brhadaranyokopanishad

कृष्णशुक्ल-यजुर्वेदयोः भेदः ॥ Differences between Krishna and Shukla Yajurveda

Following are few differences between Krishna and Shukla Yajurveda presented by Pt. Rishiram Regmi.

S. No	कृष्ण-यजुर्वेदः ॥ Krishna Yajurveda	शुक्ल-यजुर्वेदः ॥ Shukla Yajurveda
1	Mantras in both metrical and prose forms	Mantras purely with chandas (metrical) only.
2	Irregularly arranged ऋषि-s || rishis, देवता-s || devatas and छन्दस् || chandas in तैत्तिरीय-सर्वानुक्रमणिका ॥ Taittriya Sarvanukramanika (अस्तव्यस्तता)	Organized structure is seen in अनुक्रमणिका ॥ Anukramanika
3	Mantras and Brahmanas interspersed (मन्त्र-ब्राह्मणयोः सङ्कीर्णता)	Only Mantras are present. Brahmana part is separate.
4	Usage of one mantra in different contexts (प्रयोग-विविधता)	Usage of mantra in various contexts are not seen in this shakha.
5	Mantras are incomplete and filled by the कल्पसूत्र-मन्त्राः ॥ Kalpasutra mantras. (मन्त्र-अपूर्णता)	Kalpa sutras are not required for completion of mantras.
6	Existence of सारस्वत् ॥ Saraswat and आर्षेय ॥ Arsheya systems of classification in पदपाठः ॥ padapatha (पाठद्वैविद्यम्)	No such classification is present.
7	Follows ब्रह्मसम्प्रदायः ॥ Brahma Sampradaya	Follows आदित्य-सम्प्रदायः ॥ Aditya Sampradaya
8	Widely followed in Southern parts of India	Widely followed in Northern parts of India
9	Given by वैशम्पायन-ऋषिः ॥ Rishi Vaisampayana	Given by याज्ञवल्क्य-ऋषिः ॥ Rishi Yajnavalkya (Shatapatha Brahmana 14.9.5.33)

विषयम् || Vishayam (Content)

Whether Krishna or Shukla, both the shakhas of Yajurveda deal primarily with the कर्मकाण्डः ॥ karmakanda and are also called यज्ञकाण्डः ॥ yajnakanda. All the shakha texts deal with detailed descriptions of श्रौतयज्ञाः ॥ Shrauta yajnas like राजसूयः ॥ Rajasuya, वाजपेयः ॥ Vajapeya, सोमयागः ॥ Somayaga etc. Krishna Yajurveda is considered older than the Shukla Yajurveda.

It may be noted that while in Rigveda the text is organized according to rishis as mantra drastas, in Yajurveda the text is given according to the yajnas. It is a compilation of ritual offering formulas that were said by a priest while a यजमानः ॥ yajamana performed ritual actions such as those before the yajna fire. Yajurveda samhita includes mantras that are distinct yet borrow and build upon the foundation of verses in Rigveda. Unlike the सामवेदः ॥ Samaveda which is almost entirely based on Rigveda mantras and structured as songs, the Yajurveda samhitas are in prose and linguistically, they are different from other Vedic texts. Yajurveda text is not just related to rituals or sacrifice, it includes the largest collection of primary Upanishads, influential to various schools of Hindu philosophy.

सामवेदः || Samaveda

व्युत्पत्तिः ॥ Etymology

तल्लक्षणमाह जैमिनिः - गीतेषुसामाख्या इति गीयमानेषु मन्त्रेषु सामसंज्ञेत्यर्थः इति ||

tallakṣaṇamāha jaiminiḥ - gīteṣusāmākhyā iti gīyamāneṣu mantreṣu sāmasaṃjñetyarthaḥ iti ||

According to Jaimini (Shabdakalpadruma), Mantras which are to be sung are called as साम ॥ Sama. According to Brhadaranyaka Upanishad (1.3.22), Sama is derived as follows:

सा चामश्चेति तत्साम्नः सामत्वम् । sā cāmaśceti tatsāmnaḥ sāmatvam । 

Meaning : सा stands for Rk mantra and अम stands for गान ॥ Gana (gandhara etc svaras) and forms साम ॥ Sama when combined.

Along with the preparation of Soma rasa(सोमरसः), praising the devatas by singing Samagana (सामगानम्) is an important aspect during Somayajna (सोमयज्ञः). Instruments such as veena, dundubhi flute and other instruments were used. Shatapata Brahmana states that without Samagana, Somayajna does not yield the desired results.

सामवेद-विभजनम् ॥ Samaveda Vibhajana

Samaveda Samhita (सामवेद-संहिता) is the shortest of all the vedas given to the world by Jaimini. Many Sama mantras are derived from the eighth and ninth Mandalas of the Rigveda. The division of the Samaveda text is as follows :

आर्चिकः ॥ Archika ►	अध्यायः ॥ Adhyaya ►	खण्डः ॥ Khanda ►	मन्त्रः ॥ Mantra

Adhyaya is also called as Prapathaka. Thus the structure is as follows

• Each Archika is divided into several sections called Adhyayas.
• Each Adhyaya consists of two Khandas.
• Each Khanda is made up of Dashati. 
• Each Dashati contains a number of mantras (rks). 

According to some scholars the Rks are of two types - गेय (Song format) and अगेय (Not in Song format). Samaveda is composed of गेय-ऋक् (Song format of Rks) called as आर्चिक (Archika) and गेय-यजुस् (Song form of Yajus) called as स्तोक (Stoka).

The Samaveda comprises two major parts.

1. आर्चिकः ॥ Archika or the Mantras (hence called समांहितः ॥ Samamhita). The Archika is also separated in two - the Purvarcika and the Uttararcika.
2. गान ॥ Gana or the Melody
3. Purvarchika contains 6 adhyayas and a total of 650 rk mantras. While the mantras of the first five adhyayas are called ग्राम-गान the mantras of the sixth adhyaya is sung in forests.
4. Uttarchika contains 9 prapathakas with a total of 1225 mantras.

The Kauthuma Samaveda Samhita (कौथुम-सामवेद-संहिता) consists of 1875 mantras, taken almost entirely (except for 75 mantras) from the Rigveda Shakala samhita (ऋग्वेद-शाकल-संहिता). Scholars opine that the 75 mantras are also taken from the lost shakhas of Rigveda (Shankhayana (शाङ्खायन) and others), while some others opine that they are the original mantras of Samaveda.

Jaimineeya Samhita (जैमिनीय-संहिता) of Samaveda is divided into Purva Archika (पूर्वाचिकः) containing 646 mantras and Uttara Archika (उत्तरार्चिकः) 1041, totaling to 1687 mantras.

शाखाः ॥ Shakhas

सहस्त्रवर्त्मा सामवेदः | sahastravartmā sāmavedaḥ |

According to महाभाष्यम् ॥ Mahabhashya, चरणव्यूहम् ॥ Charanavyuha, मुक्तिकोपनिषद् ॥ Muktikopanishad, अथर्वणपरिशिष्टम् ॥ Atharvana Parishisth, सर्वानुक्रमणिका ॥ Sarvanukramanika and महाभारतम् ॥ Mahabharata, this Veda is said to have 1000 Shakhas. This aspect is also found to be mentioned in पुराण-s || Puranas. There is an interesting ancedote mentioned by Pt. Ramshankar Bhattacharya that सामशाखाः ॥ Samashakhas were destroyed by इन्द्रः ॥ Indra. Also a mention was made about the different सामशाखा ॥ Samashaka preachers being wiped out by a natural calamity (See Page 21 of Reference 1). However, there are different versions of scholars about the loss of shakhas of Samaveda, but many opine that an innumerable number of Samaganas could have existed.

Some Samaganas that have found a mention in other texts include - बृहत् रथन्तर, वैराज, ज्येष्ठ, रैवत among others that are definitely more than 1000 which may be the reason why the word "सहस्त्र" or thousand may be justified. Some shakhas of Samaveda that were mentioned in few ancient texts are

सात्यमुग्राः, नैगेयाः, शार्दूलाः, वार्षगण्याः, गाैतमाः, भाल्लविनः, कालबविनः, शाट्यायनिनः. रौरुकिणः. कापेयाः, माषशराव्यः, करद्विषः, शाण्डिल्याः, ताण्ड्याः

sātyamugrāḥ, naigeyāḥ, śārdūlāḥ, vārṣagaṇyāḥ, gāaitamāḥ, bhāllavinaḥ, kālabavinaḥ, śāṭyāyaninaḥ. raurukiṇaḥ. kāpeyāḥ, māṣaśarāvyaḥ, karadviṣaḥ, śāṇḍilyāḥ, tāṇḍyāḥ

Other shakhas of Samaveda include:

राणायनः || Ranayana, सात्यमुग्र-व्यासः || Satyamugra-vyasa, भागुरिः || Bhaguri, औलुण्डिः || Aulundi, गौल्मुलिवः || Gaulmuliva, भानुमानः || Bhanumana, औपमन्यवः || Aupamanyava, दारालः || Darala, गार्ग्यः || Gargya, सावर्णिः || Sarvani, वार्षगणिः || Varshagani, कुथुमिः || Kauthumi, शालिहोत्रः || Shalihotra, जैमिनिः || Jaimini while according to Sanskrita Saahitya Charitra, सात्यमुग्रः || Satyamugra, व्यासः || Vyasa, are separate shakhas, few others namely मानेपमन्यवः || Manepamanyava, काराटिः || karati, मशका || Mashaka are mentioned in addition to those given earlier.

Presently only three शाखाः ॥ shakhas are available.

1. कौथुम || Kauthuma
2. राणायनीय || Ranayaniya
3. जैमिनीय || Jaiminiya

Kauthuma (कौथुम) is the widely followed shakha, mainly by Nagara brahmins of Gujarat, while Ranayaniya is seen among the people of Maharashtra and Jaiminiya shakha is seen in Tamilnadu.

विषयम् || Vishayam (Content)

The Samaveda is compiled exclusively for ritual application, for its verses are all meant to be chanted at the ceremonies of the Soma-sacrifice and procedures derived from it. The Samaveda is, therefore, specially intended for the Udgatr priest.

The special virtue of Samaveda is that although its mantras are from the Rigveda, they are set to music which is greatly conductive to the spiritual evolution of a human being and to qualify oneself for receiving the grace of the devatas.

Sri Krishna says in श्रीमद् भगवद्गीता ॥ Shrimad Bhagavadgita (Ch.10 Verse 22) 

वेदानां सामवेदोस्मि । vedānāṃ sāmavedosmi ।

Meaning : Among the Vedas, I am the Samaveda. 

ब्राह्मणानि आरण्यकानि उपनिषदः च ॥ Brahmanas, Aranyakas and Upanishads

ब्राह्मण-s || Brahmanas, आरण्यक-s || Aranyakas and उपनिषद्-s || Upanishads affiliated to this Samhita are

1. ताण्ड्य-महाब्राह्मणम् ॥ Tandya Maha Brahmana, the biggest and most important. The other seven ब्राह्मण-s || Brahmanas namely षड्विंशब्राह्मणम् ॥ Shadvimshabrahmana, आर्षेयब्राह्मणम् ॥ Arsheyabrahmana, समविधानब्राह्मणम् ॥ Samavidhanabrahmana, देवताध्यायब्राह्मणम् ॥ Devatadhyayabrahmana,छान्दोग्य-उपनिषद्-ब्राह्मणम् ॥ Chanddogyopanishad-brahmana, वंशब्राह्मणम् ॥ Vamshabrahmana and संहितोपनिषद्-ब्राह्मणम् ॥ Samhitopanishadbrahmana.
2. One आरण्यकम् ॥ Aranyaka of this संहिता ॥ Samhita is available which is called तलवकार ॥ Talavakara or जैमिनीय-आरण्यकम् ॥ Jaiminiya Aranyaka.
3. छान्दोग्य-उपनिषद् ॥ Chandogya Upanishad
4. केनोपनिषद् ॥ Kenopanishad, also known as तलवकारोपनिषद् ॥ Talavakaropanishad.

अथर्ववेदः || Atharvaveda

व्युत्पत्तिः ॥ Etymology

अथर्वण ॥ Atharvana or अथर्ववेदः ॥ Atharvaveda (Samskrit : अथर्वण or अथर्व).

Here, थु्र्वी हिंसायाम् धातु || thurvī hiṃsāyām dhātu undergoes change into थर्व. अथर्व means that which is devoid of हिंसा ॥ himsa (harm to others).

Other names of this Veda include ब्रह्मवेदः ॥ Brahmaveda, क्षत्रवेदः ॥ Kshtraveda (as it contains a information about राजनीतिः ॥ rajaneeti or statecraft and administration for kings), भिषग्वेदः ॥ Bhishagveda (as it contains information about diseases and their cure), अङ्गीरोवेदः ॥ Angiroveda and अथर्वाङ्गीरोवेदः ॥ Atharvangiroveda. It is called as ब्रह्मवेदः ॥ Brahmaveda due to the following 3 reasons

1. In यज्ञकर्माणि ॥ Yajna karmas, ब्रह्मा ॥ Brahma is the ऋत्विक् ॥ Rtvik who oversees the यज्ञः ॥ yajna.
2. Contains the knowledge of ब्रह्मन् ॥ Brahman
3. The mantras of this veda were revealed to the rishi named ब्रह्मा ॥ Brahma.

अथर्ववेद-विभाजनम् ॥ Atharvaveda Vibhajana

The अथर्ववेद-संहिता ॥ Artharvaveda Samhita is the text revealed to the अथर्वन् || Atharvan and अङ्गिरसः || Angirasa rishis. अथर्वसंहिता ॥ Atharvasamhita of शौनक-शाखा ॥ Shaunaka shakha has the following divisions of the text.

काण्डः ॥ Kanda ►	सूक्तम् ॥ Sukta ►	प्रपाठकः ॥ Prapathaka ►	मन्त्रः ॥ Mantra

It has 20 काण्डाः ॥ Kandas, 760 / 730 / 731 सूक्तानि ॥ Suktas, 36 प्रपाठकाः ॥ Prapathakas and 5987 (5977) मन्त्राः ॥ mantras. Most of the mantras are metrical, but some sections are in prose. About 20% of the mantras are from Rigveda.

शाखाः ॥ Shakhas

According to अथर्वणपरिशिष्टम् ॥ Atharvana Parishista, चरणव्यूहम् ॥ Charanavyuha, प्रपञ्चहृदयम् ॥ Prapanchahrdaya, पतञ्जलेः महाभाष्यम् ॥ Patanjali's Mahabhashya and कूर्मपुराणम् ॥ Kurma Purana and सर्वानुक्रमणी ॥ Sarvanukramani, अथर्वणवेदः ॥ Atharvanaveda had 9 शाखाः ॥ shakhas. Another version of सर्वानुक्रमणी ॥ Sarvanukramani and मुक्तिकोपनिषद् ॥ Muktikopanishad mention the existence of 50 shakhas. The 9 shakhas according to चरणव्यूहम् ॥ Charanavyuha are, slightly different from other versions, given as follows:

पैपलादाः ॥ Paippalada, स्त्रौदाः || Strauda, शौनकीयाः || Shaunakeeya, जाजलाः || Jajala, देवदर्शाः || Devadarsha, चारणविद्याः || Charanavidya, स्त्रौदाः || Strauda, जलदाः || Jalada, ब्रह्मवादः || Brahmavada

According to other versions the nine shakhas are

पैपलादाः || Paippalada, स्त्रौदाः || Strauda or तौदः || Tauda, मौदः ॥ Mauda , शौनकः ॥ Shaunaka, जाजलः ॥ Jajala, जलदः ॥ Jalada, ब्रह्मवादः || Brahmavada, देवदर्शः ॥ Devadarsha, चारणवैद्यः ॥ Charanavaidya

Out of the 9 Shakhas known only two are available now. They are,

1. पैप्पलादः ॥ Pippalada (incomplete version)
2. शौनकः ॥ Shaunaka

देवताः छन्दसः ऋत्विक् च ॥ Devatas, Chandas and Rtvik

Like ऋग्वेदः ॥ Rigveda from where अथर्वणवेदः ॥ Atharvanaveda takes a significant part, the छन्दस् ॥ chandas here include अनुष्टुप् ॥ Anustup, त्रिष्टुभप् ॥ Tristup along with many other new छन्दस् ॥ chandas or metrical forms. Worship of many देवताः ॥ devatas is also seen along with the acceptance of the Supreme Being. The ऋत्विक् ॥ rtvik of अथर्ववेदः ॥ Atharvaveda is ब्रह्मा || Brahma who supervises the conduct of the यज्ञ-s ॥ Yajnas.

विषयम् ॥ Content

As the अथर्ववेदसंहिता ॥ Atharvaveda Samhita has some special features, it stands apart from the other three Vedas. It deals more with worldly things than with the other worlds and the यज्ञाः ॥ yajnas mentioned here are utilized as a means to them. Amidst mundane subjects high philosophical ideas are also found in this Veda.

This Veda contains many types of mantras for the following worldly or materialistic purposes

• To ward off evils and hardship, snakes, and supernatural forces such as demons.
• To destroy enemies
• Marriage, cremation and other संस्काराः ॥ samskaras
• Description of diseases,their cure and herbal remedies
• For prolonging life
• For fulfilling one’s desires
• For wealth, trade and commerce
• राजनीतिः ॥ Rajaneeti includes statecraft, defense systems of the country, training for soldiers, winning in wars.
• Related to Supreme Reality, Immortality and other philosophical matters.
• Creation and emergence of the Universe. .

The अथर्ववेदः ॥ Atharvaveda was not considered as a Veda in the Vedic era, and was accepted as a Veda during later ages; though some schools do not consider it even in modern era.

The Atharvaveda has been a primary source for information about Vedic culture, their customs and beliefs, the social economic conditions, agricultural and scientific matters, the requirements of people in everyday life in Vedic era ranging from मन्त्राः ॥ mantras for snakes to those associated with kings and governance.

प्रसिद्धाः विषयाः ॥ Famous Aspects

• पृथ्वीसूक्तम् || Prthvi Sukta
• मधुविद्यासूक्तम् ॥ Madhuvidya Sukta
• काण्ड ॥ Kanda 15 is called व्रात्यकाण्डः || Vratya kanda. It deals about people whose origin and nature is debated by many scholars, and they did not follow any kind of वैदिकक्रियाः ॥ vaidika kriyas, nor had respect for any rituals.

ब्राह्मणानि आरण्यकानि उपनिषदः च ॥ Brahmanas, Aranyakas and Upanishads

Only one ब्राह्मणम् ॥ Brahmana called गोपथब्राह्मणम् ॥ Gopatha Brahmana has been discovered. No आरण्यकम् ॥ Aranyaka of this वेदः ॥ Veda has come to light so far.

There are a number of Upanishads which are associated with this Veda. The well known Upanishads belonging to this Veda are :

1. प्रश्न-उपनिषद् ॥ Prashna Upanishad
2. मुण्डक-उपनिषद् ॥ Mundaka Upanishad
3. माण्डूक्य-उपनिषद् ॥ Mandukya Upanishad

Sub Classification of Vedas

Different texts of Vedic literature is further classified as follows.

संहिताः || Samhitas

संहिता-s || Samhitas deal primarily with याग-s || yagas and are collections of मन्त्राः ॥ mantras in praise of deities for attaining prosperity in the world and happiness hereafter. There are four Vedic Samhitas: the ऋग्वेदः ॥ Rigveda, सामवेदः ॥ Samaveda, यजुर्वेदः ॥ Yajurveda, and अथर्ववेदः ॥ Atharvaveda, most of which are available in several शाखाः ॥ shakhas (recensions).

यागाः ॥ Yagas are of three types :

• एकाहः ॥ Ekaha: A yaga that is completed in one day is called Ekaha. Ex: ज्योतिष्टोमः ॥ Jyotishtoma.
• Ahina: A yaga that is lasts between 2 to 12 days is called Ahina or sutya. Ex: a 12 day Sutyaka is Poundarika
• सत्रयागः ॥ Satrayaga: A यागः ॥ yaga that lasts from 12 days to a few years is called सत्रम् ॥ Satra. Ex : Gavamanas

In these samhitas, all कर्म-s || karmas are described, they are of four types :

• नित्यकर्म ॥ Nityakarma: actions that are prescribed to be performed on a daily basis
• नैमित्तिककर्म ॥ Naimittika karma
• काम्यकर्म ॥ Kamya karma
• निषिद्धकर्म ॥ Nishiddha karma

In some contexts, the term Veda is used to refer to these Samhitas. This is the oldest layer of Vedic texts, apart from the Rigveda, which is the oldest text in the world.

This portion is mainly meant for ब्रह्मचारी-s || Brahmacharis, those who are in the first stage of their lives.

ब्राह्मणानि || Brahmanas

आपस्तम्बः || Apastamba defines ब्राह्मण-s || Brahmanas as

‘कर्मचोदना ब्राह्मणानि || karmacodanā brāhmaṇāni’

Meaning: ब्राह्मण-s || Brahmanas are injunctions for the performance of sacrificial rites (Apastamba Shrau. Sut. 34 and 35).

Some believe that what are not mantras are ब्राह्मण-s || brahmanas (जैमिनीयपूर्वमीमांसा ॥ Jaimineeya Purvamimamsa 2.1.33)

ब्राह्मण-s || Brahmanas though are not metrical like the Vedic mantras contain prose with पाठपद्धतिः ॥ patha paddhati (recitation methods) to chant them. They are commentaries or explanation of ceremonial श्रौतयज्ञाः ॥ Shrauta yajnas giving the meaning of मन्त्राः ॥ mantras in Vedic Samhitas of the four Vedas and depict the socio-economic conditions and religious aspects of the era. They also contain some legends and debates about a few differences in the rituals. Each Vedic shakha (school) has its own operating manual-like ब्राह्मण ॥ Brahmana text, most of which have been lost. A total of 19 Brahmana texts have survived into modern times: two associated with the Rigveda, six with the Yajurveda, ten with the Samaveda and one with the Atharvaveda.

Each of the Brahmanas is associated with one of the Samhitas or its recensions. The Brahmanas may either form separate texts or can be partly integrated into the text of the Samhitas. They may also include the आरण्यक-s || Aranyakas and उपनिषद्-s || Upanishads. The substance of the Brahmana text varies with each Veda.

This portion of a Veda guides people in the performance of Vedic Karmas or sacrificial rituals; they are the prose explanations of the method of using the mantras in the Yajnas and other rituals. Brahmana is suitable for the गृहस्थ-s || Grhasthas (the householders), those belonging to the second stage in life.

आरण्यकानि || Aranyakas

आरण्यक-s || Aranyakas, "wilderness texts" or "forest treatisies" :

अरण्येऽधीयूरान् || araṇye'dhīyūrān ||

Meaning: Texts to be studied in forests

As mentioned in तैत्तिरीय-आरण्यकम् ॥ Taittiriya Aranyaka, they were composed by people who meditated in the woods as recluses and are the third part of the Vedas. The texts contain discussions and interpretations of ceremonies, from ritualisitic to symbolic meta-ritualistic points of view.

This text is unavailable (as for अथर्वणवेदः ॥ Atharvanaveda) or found as the last part of the ब्रामणानि ॥ Brahmanas, or are completely separated from the ब्राह्मणानि ॥ Brahmanas. For example, the last काण्ड ॥ kanda of शतपथ-ब्राह्मणम् ॥ Shatapata Brahmana is आरण्यकम् ॥ Aranyaka for शुक्लयजुर्वेदः ॥ Shukla Yajurveda, whereas in कृष्णयजुर्वेदः ॥ Krishna Yajurveda, the तैत्तिरीय-ब्राह्मणम् ॥ Taittiriya Brahmana and आरण्यकम् ॥ Aranyaka are completely separate.

आरण्यक-s || Aranyakas, however, neither are homogeneous in content nor in structure. They are a combination of instructions and ideas, and some include chapters of उपनिषद्-s || Upanishads within them. Two theories have been proposed on the origin of the word आरण्यक ॥ Aranyaka. One theory holds that these texts were meant to be studied in a forest while the other holds that the name came from these being the manuals of allegorical interpretation of sacrifices, for those in वानप्रस्थः || Vanaprastha (retired, forest-dwelling) stage of their life, according to the historic age-based आश्रम ॥ Ashrama system of human life.

The Aranyaka portion is addressed to the people of that category offering a substitute for rituals. They teach methods of meditation based upon symbolical interpretations of sacrificial rites. It is a process of performing यज्ञ-s || Yajnas and sacrifices at the mental level. For example: बृहदारण्यक-उपनिषद् ॥ Brhadaranyaka Upanishad starts with such analytical mental performance of अश्वमेधयज्ञः ॥ Ashwamedha Yajna. The Aranyakas are intended for the Vanaprasthas or people who prepare themselves for the last stage in life i.e. सन्यासः ॥ Sanyasa. Aranyakas form the transition link between the ritual of the Brahmanas and the philosophy of the Upanishads.

उपनिषदः || Upanishads

The number of works that go by the name Upanishad and available today in print exceeds 200. The मुक्तिकोपनिषद् ॥ Muktikopanishad gives a list of 108 Upanishads. However, the principal Upanishads are accepted to be those which श्रीआदिशङ्कराचार्यः ॥ Sri Adi Shankaracharya chose to comment upon.

श्रीशङ्कराचार्यः ॥ Sri Shankaracharya was the earliest commentator on the Upanishads. He chose only 10 Upanishads for his commentaries. According to some scholars, he commented upon 11 Upanishads. He refers to 4 more Upanishads in his commentary on ब्रह्मसूत्रम् ॥ Brahmasutra namely श्वेताश्वतर-उपनिषद् ॥ Shvetashvatara  Upanishad, कौषीतकी उपनिषद् ॥ Kousitaki Upanishad, जाबाल-उपनिषद् ॥ Jabala Upanishad, महानारायण-उपनिषद् ॥ Mahanarayana Upanishad, and पैङ्गल-उपनिषद् ॥ Paingala Upanishad.

Considering the ones chosen by him for commenting as reference material and as the most ancient and authentic, they are termed as major or principal Upanishads. We may list them as follows:

TEN MAJOR UPANISHADS (Based on Sri Adi Shankaracharya's Commentaries)

1. ईशावास्य/ईशोपनिषद् ॥ Ishavasya/Isopanishad
2. केन-उपनिषद् ॥ Kena Upanishad
3. कठ-उपनिषद् ॥ Katha Upanishad
4. प्रश्न-उपनिषद् ॥ Prashna Upanishad
5. मुण्डक-उपनिषद् ॥ Mundaka Upanishad
6. माण्डूक्य-उपनिषद् ॥ Mandukya Upanishad
7. तैत्तिरीय-उपनिषद् ॥ Taittiriya Upanishad
8. ऐतरेय-उपनिषद् ॥ AitareyaUpanishad
9. छान्दोग्य-उपनिषद् ॥ Chandogya Upanishad
10. बृहदारण्यक-उपनिषद् ॥ Brhadaranyaka Upanishad

The Upanishads are the concluding portions of the Vedas which discuss philosophical issues both in prose and metrical forms. They are commonly referred to as वेदान्तः || Vedanta, variously interpreted to mean either the "last chapters, parts of the Vedas" or "the object, the highest purpose of the Veda". The concepts of ब्रह्मन् || Brahman (Ultimate Reality, परमात्मा ॥ Paramatma), आत्मन् || Atman (Soul, Self, जीवात्मा ॥ Jivatma) and liberation of soul (मुक्तिः ॥ Mukti/ मोक्षः ॥ Moksha) are central ideas in all the Upanishads and primarily focus on routes for obtaining ब्रह्मविद्या ॥ Brahmavidya which on practice leads one to मुक्तिः ॥ Mukti. The Upanishads are the foundation of Hindu philosophical thought and its diverse traditions.

They are the essence of the Vedas containing their knowledge aspects along with explanation of कर्म-s || karmas (as in Upakosala's tending to fires in छान्दोग्य-उपनिषद् ॥ Chandogya Upanishad). The philosophy of the Upanishads occupies the highest pedestal in the spiritual knowledge. They speak about the identity of the Supreme Eternal Soul, the ब्रह्मन् ॥ Brahman, the individual soul, the आत्मन् ॥ Atman, their mutual relationship, the Universe (जगत् ॥ jagat) and man’s place in it. In short, they deal with जीवात्मा || Jivatma, परमात्मा || Paramatma, जगत् || Jagat, अविद्या ॥ Avidya, कर्मफलम् ॥ Karmaphalam, पुनर्जन्म ॥ Punarjanma and जगदीश्वरः || Jagadishvara.

आरण्यक-s || Aranyakas are sometimes identified as कर्मकाण्ड ॥ karma-kanda (ritualistic section), while the Upanishads are identified as ज्ञानकाण्ड ॥ jnana-kanda (spirituality section). In an alternate classification, the early part of Vedas are called संहिताः ॥ Samhitas and the commentary are called the ब्राह्मण-s || Brahmanas which together are identified as the ceremonial कर्मकाण्डः ॥ karma-kanda, while आरण्यक-s || Aranyakas and उपनिषद्-s || Upanishads are together referred to as the ज्ञानकाण्डः ॥ jnana-kanda.