Rigveda
Contains mainly mantras in praise of various vedic deities and prayers to them.
It is divided in two ways.
8 ashtakas comprising of 64 adhyayas
OR
10 mandalas comprising of 85 anuvakas
In total there are 1028 suktams made up of 10552 mantras. A suktam is a collection of mantras on a particular subject.
Originally there were 21 branches of this veda, but now only to ie:- Bhashkala and Sakala are existing.
The sub texts of this veda are
Brahmanas ( procedural instructions) - Kaushitaki, Sangrayana and Aithareya
Aranyakas - Kaushitaki and Aithareya
Upanishads - Kaushitaki and Aithareya
Gruhya sutra - Asvalayana
Yajurveda
There are two schools of yajurveda. The shukla yajurveda and the krishna yajurveda. The main difference is that in shukla yajurveda we find mantras alone whereas krishna yajurveda is a mix of mantras and the relevant brahmana bhaga also.
Yajurveda consists mainly of procedural mantras used in yajnas and it is in prose.
The shukla yajurveda has got two main branches as of today.
1. Vajasaneyi madhyandiniya mainly found in north india 2. Kanva mostly found in Tamil Nadu.
Vajasaneyi samhita consists of 303 anuvakas made up of 1975 kandikas classifiec into 40 chapters. Kanva samhita againa has got 40 chapters divided into 328 anuvakas comprising of 2086 kandikas.
The krishna yajurveda is made up of 7 kandas divided into 44 prasnas. There are 651 anuvakas made up of 2198 panchashatis (group of fifty words).
Sub texts of shukla yajurveda
Brahmanam - Shatapatha brahmanam
Upanishad - Isha and Brihadaranyaka
Sub texts of krishna yajurveda
Brahmanam - Taittiriya brahmanam
Aranyaka - Taittiriya aranyaka
Upanishad - Taittiriya, Katha and Maitrayani
Gruhya sutra - Apastamba, Bodhayana
Samaveda
Samaveda consists of songs. Of the 1875 verses of samaveda, 1800 are from rigveda.
It consists of two parts
Purvarchika consisting of 6 chapters with 650 mantras and
Uttararchika consisting of 21 chapters with 1225 mantras.
The main branches are kauthuma and ranayaniya.
Atharva veda
Atharva veda comprises of mantras used for all worldly purposes such as healing, penances, fulfillment of wishes etc and also adhyatma.
The main branches are Saunaka and Paippalada.
Saunaka samhita consists of 5977 mantras arranged into 730 suktams in 20 chapters.
Sub texts of atharva veda
Brahmanam - Gopatha
Upanishad - Mundaka, Mandukaya.