What is the Googloplex?

A googolplex is the number 10googol, which can also be written as the number 1 followed by a googol of zeros (i.e. 10100 zeros). : 1 googolplex : = 10googol : = In 1938, Edward Kasner's nine-year-old nephew Milton Sirotta coined the term googol; Milton then proposed the further term googolplex to be "one, followed by writing zeroes until you get tired". Kasner decided to adopt a more formal definition "because different people get tired at different times and it would never do to have [the boxer champion] Carnera be a better mathematician than Dr. Einstein, simply because he had more endurance".[1]