Yuga

1. Satya Yuga[?] or Krita Yuga[?] - 1,728,000 years
2. Treta Yuga[?] - 1,296,000 years
3. Dwapar Yuga[?] - 864,000 years
4. Kali Yuga - 432,000 years

Right now we are living in the Kali Yuga, which is the dark age. Satya Yuga is the golden age.

Upon conclusion of this cycle, the world is essentially "rebooted" and the cycle begins anew.

See also

• Metrics of time in Hinduism