 The ease of copying depended on the system; Jerry Pournelle wrote in "BYTE" in 1983 that ""CP/M doesn't lend itself to copy protection"" so its users ""haven't been too worried"" about it, while ""Apple users, though, have always had the problem.So have those who used TRS-DOS, and I understand that MS-DOS has copy protection features"".Apple and Commodore 64 copy protection schemes were extremely varied and creative because most of the floppy disk reading and writing was controlled by software (or firmware), not by hardware.