10,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000

A googol is the large number 10^100; that is, the digit 1 followed by 100 zeroes:

10,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000,­000.

The term was coined in 1938^[1] by 9-year-old Milton Sirotta, nephew of American mathematician Edward Kasner. Kasner popularized the concept in his 1940 book Mathematics and the Imagination.

A googol has no particular significance in mathematics, but is useful when comparing with other very large quantities such as the number of subatomic particles in the visible universe or the number of hypothetically possible chess games. Edward Kasner used it to illustrate the difference between an unimaginably large number and infinity, and in this role it is sometimes used in teaching mathematics.

A googol is approximately 70!