தொல்காப்பியம் கூறும் ரகசியம் Tholkappiam's Secret .
The Tholkāppiyam (Tamil: தொல்காப்பியம், literature) is a work on the grammar of the Tamil language and the earliest extant work of Tamil literature and linguistics. It is written in the form of noorpaa or short formulaic compositions and comprises three books - the Ezhuttadikaram, the Solladikaram and the Poruladikaram. Each of these books is further divided into nine chapters each. While the exact date of the work is not known, based on linguistic and other evidence, it has been dated variously between the 5th century BCE and the 2nd century CE. Some modern scholars prefer to date it not as a single entity but in parts or layers.There is also no firm evidence to assign the authorship of this treatise to any one author.