In the late 1970s-early 1980s, a myriad of cassette-tape based storage systems started being sold as an option for the “home computer” market, the plastic-wrapped, cheaper but all-in-one-already-built computers being sold by various companies in a bid to become dominant in the market. (Even the ultimately-winning IBM PC had a cassette port, although the system was generally sold with a floppy drive and it’s unlikely any significant number of people used it.) different approaches to how they wrote data on tape, and read it back, with speed differing notably between them.
By the late 1980s, it was rapidly becoming unusual to depend on data tapes to read and load to home computers, and the jump to floppies and ultimately hard drives and CD-ROMs came with phone number database mass adoption in the 1990s.
But it wasn’t completely gone, either.
In this zone, this Venn Diagram of a market of computer end-users with this exhausting set of possible media input devices, commercial creators had a heck of time. Intent on reaching every market they reasonably could, multiple formats meant multiple releases of the same programs.
Does this mean that Activision had to spend the money to make a floppy disk version and a computer cassette version of the game Ghostbusters for Commodore 64? Yes, in fact they did. (One distributor, HES, even made a cartridge version, which was an Australia-only hack that put the contents onto a cartridge and forced a loading as if it was a floppy.)