"According to Charaka Samhita and Sushruta Samhita, it was Lord Brahma who composed Ayurveda and divided in to eight branches since he believed that man had limited intelligence. The branches of Ayurveda described are: Kayachkitsa (Internal medicine); Shalakya (Surgery of head and neck, optholomology and otorhinolaryngology; Shalya (Surgery); Vishagarva virodhika tantra (Toxicology); Bhootavidya (Psychiatry); Kaumarbhrutya (Pediatrics); Rasayna tantra (Gerontology or science of rejuvenation); and Vajikarana tantra (Science of fertility)."