Manu is a term found with various meanings in Hinduism. In early texts, it refers to the archetypal man, or to the first man (progenitor of humanity). The Sanskrit term for 'human', means 'of Manu' or 'children of Manu'.
In later texts, Manu is the title or name of fourteen Kshatriya rulers of earth, or alternatively as the head of dynasties that begin with each cyclic kalpa when the universe is born anew.
The title of the text Manusmriti uses this term as a prefix, but refers to the first Manu – Svayambhuva, the spiritual son of Brahma.
In the earliest mention of Manu, in the Rigveda, Manu is only the ancestor of the "Five Peoples", or "Páñca Jánāḥ"
(the five tribes being the Anus, Druhyus, Yadus, Turvashas, and Purus). The Indo-Aryans considered all other peoples to be a-manuṣa. Later, in the Hindu cosmology, each kalpa consists of fourteen Manvantaras, and each Manvantara is headed by a different Manu.
The current universe is asserted to be ruled by the 7th Manu named Vaivasvata. Vaivasvat was the king of Dravida before the great flood. He was warned of flood by the Matsya avatar of Vishnu&built a boat that carried Vedas,Manu's family &the seven sages to safety,helped by Matsya