1. A point-of-sale terminal for recording transaction data, said terminal comprising: programmable processing means including read/write addressable memory for holding both applications programs and data, and further including read-only memory holding routines for loading different ones of said applications programs into said read/write memory; direct-access storage means coupled to said processing means and adapted to read and write a single removable, non-volatile storage medium holding both said applications programs and said transaction data; input means coupled to said processing means for receiving said transaction data from an operator; output means coupled to said processing means for displaying said transaction data; cash-handling means controlled by said processing means in response to said applications programs; and enclosure means for housing all the above means in a single physical package, said enclosure means further including means for inserting and removing said removable storage medium in said direct-access storage means.