The Vedas (Sanskrit véda वेद "knowledge") are a large body of texts originating in ancient India. Composed in Vedic Sanskrit, the texts constitute the oldest layer of Sanskrit literature and the oldest scriptures of Hinduism.
Source Of Veda
The Veda is said to have been revealed by Brahma to ancient Rishis. The mode of communication was known as Sruti (what is heard in the minds of a person).
The Four Samhitas
Due to huge amount of the text present in the Veda, it was impossible for a single human to memorize, recite and understand the Veda. Vyasa Muni then decided to break the Veda into four Samhitas and simplify the same. The four Samhitas were as follows: