On "programmable" home gaming consoles with exchangeable cartridges:

Old style "dedicated" video games that plug into a TV set and offer the choice of a few bat-and-ball contests are becoming a little long in the tooth. "Semi-programmable" games cost around £30. These take cartridges to expand the range of games but the complexity of the games is still limited and their graphics are poor. For a wide choice of complex games, and good colour graphics, go for a microprocessor-based "fully programmable" system. There are now four different—and of course wholly incompatible—programmable games systems on the British market. The cheapest, at about £80, appears under three brand names—Prinztronic VC 6000, Radofin 1292 and Acetronic MPU 1000—but with the same 8-bit microprocessor. The Philips and Atari variants both cost about £100. Mattel's Intellivision, which is just beginning to appear in Britain and costs about £200, relies on a 16-bit chip to amass more detailed graphics.

All of these systems have plug-in cartridges that cost £15 each and contain several kilobytes of memory to store the programs for the games. But the cartridges for one system are not compatible with others although, to confuse the issue, the cartridges of some units will fit into others.