What is a googol?

The name was coined in 1920 by nine-year-old Milton Sirotta, nephew of American mathematician Edward Kasner, who popularised it in his 1940 book Mathematics and the Imagination. A googol is far larger than the estimated number of atoms in the observable universe, around 10 to the power of 80. Kasner also defined the googolplex as 1 followed by a googol zeros, a number so large that it could not be written out even if every atom in the universe were used. Google’s name came from a misspelling of googol, chosen to reflect the huge amount of information on the web.