The document provides an introduction to Charaka Samhita, one of the classic texts of Ayurveda. It discusses that Charaka Samhita was originally composed by Agnivesha around 1000BC, later revised by Acharya Charaka in the 2nd-3rd century AD, and further redacted by Dridhabala in the 4th century AD. It contains 120 chapters divided across 8 sections, covering fundamental Ayurveda principles, diagnosis, treatment, formulations and more. Several important commentaries on Charaka Samhita from 4th century onwards are also mentioned.