Treta Yuga is the second of the four yugas in Hinduism. It follows Krita Yuga. Treta Yuga lasts for 1,296,000 human years. In this yuga, Brahma promulgates the institution of a class system and the mind-born sons, the sages, lay down rules and regulations.
At the instance of Brahma, Manu and the sages narrated smarta or textual and traditional codes of religion. Mantras manifested themselves automatically to Manu and the seven sages. Later on, the mantras manifested in icons of deities.
Beauty, strength, intelligence, health, long life and righteous devotion, in addition to truth (uttering of sacred syllables), tapas (penance) and dana (religious gifts) are the hallmarks of this Treta yuga.
In Treta Yuga, dandaniti, or justice by punishment, is said to be operative and dharma (righteousness) stands on three legs.