Colleges originated as residence hall for undergraduates that provided meals and lodging and a certain level of supervision, given that many undergraduates in medieval times were teenagers. Over time, they started to provide instruction to their students to help with the final exams. This resulted in fellows joining colleges and providing supervisions. In return, fellows are given certain privileges, including housing (typically, if they’re single), a small research fund, some meals, and access to a common room, called the Senior Combination Room or SCR.