BASIC was designed as a simplified, interactive version of FORTRAN that non-experts could learn in an afternoon, but which was still powerful enough for a wide range of applications including numerical methods, simulations, data processing, and games. It was also small enough to implement effectively on a timeshared minicomputer or an 8-bit microcomputer.
Even though the Mac was GUI-based, for a time it shipped with, and promoted, HyperCard, which led to a brief explosion of user-created programs developed as HyperCard stacks.