What is a googol?

A googol is a very large number: the number 1 followed by 100 zeros, or 10¹⁰⁰. Unlike most other names for numbers, it does not relate to any other numbering scale. The American mathematician Edward Kasner first used the term in 1938; when searching for a term for this large number, Kasner asked his nephew, Milton Sirotta, then about nine years old, to suggest a name. The googolplex is 10 followed by a googol of zeros. The popular Web search engine Google.com is named after the concept of a googol.