Basically, it was a way to partition users as some form of horizontal scaling. See these two Quora posts: https://www.quora.com/How-did-Zuckerberg-code-Faceboo

Basically, it was a way to partition users as some form of horizontal scaling. See these two Quora posts: https://www.quora.com/How-did-Zuckerberg-code-Facebook-so-fast-2 https://www.quora.com/How-did-Zuckerberg-code-Facebook-so-fa... https://www.quora.com/In-what-order-did-Facebook-open-to-college-and-university-campuses https://www.quora.com/In-what-order-did-Facebook-open-to-col...