How does UIUC relate to PayPal?

The "PayPal Mafia" is a group of former PayPal employees and founders who have since founded and/or developed additional technology companies[1] such as Tesla, Inc., LinkedIn, Palantir Technologies, SpaceX, Affirm, Slide, Kiva, YouTube, Yelp, and Yammer.[2] Most of the members attended Stanford University or University of Illinois Urbana–Champaign at some point in their studies.

Most of the members of the PayPal Mafia the University of Illinois Urbana–Champaign (UIUC) at some point, as well as Stanford University.