Agastya - The father of Tamil literature and Tamil grammar called Agathiyam

 Agastya Tamil:அகத்தியர்(Also known as Father of Tamil Literature and siddha [1]),( Telugu:అగస్త్య, Kannada:ಅಗಸ್ತ್ಯ, Sanskrit:अगस्त्य,AGASTYA, Malay: Anggasta, Thai: Akkhot) is one of the Saptarishis (सप्तर्षि saptarṣi a meaning "seven sages") who are extolled at many places in the Vedas and a revered Vedic sage who is also the author of Agastya Samhita [ref: Dharma Bharathi]. Agastya is a name of Shiva too. The word is sometimes written as Agasti and Agathiyar. A-ga means a mountain, and Asti means thrower.[2] Agastya the Muni, son of Urvashi was born of both Gods, Mitra and Varuna.[2][3] Agastya is also the Indian astronomical name of the star of Canopus, is said to be the 'cleanser of waters', since its rising coincides with the calming of the waters of the Indian Ocean. He was son of Pulasthya, son of Brahma.

Siddhar[4] were spiritual adepts who possessed the ashta siddhis, or the eight supernatural powers. Sage Agathiyar is considered the guru of all Siddhars, and the Siddha medicine system is believed to have been handed over to him by Lord Muruga, son of the Hindu God Lord Shiva and Goddess Parvathi.Siddhars are the followers of Lord Shiva. Agathiyar is the first Siddhar. His disciples and other siddhars contributed thousands of texts on Siddhar litratures, including medicine and form the propounders of the system in this world.[5] He is considered as the father of Tamil literature and compiled the first Tamil grammar called Agathiyam.

It is believed that he has lived in the 6th or 7th century B.C and specialized in language, alchemy, medicine and spirituality (yogam and gnanam). There are 96 books in the name of Agathiyar.[6] However, some Tamil researchers say that Agastya mentioned in Vedas and Agathiyar mentioned in Tamil texts could be two different characters. In Tamil language the term 'Agam' means inside and 'iyar' means belong. One who belong inside (soul) is the Tamil meaning for Agathiyar.