in memory of Jerry Lawson, who invented the first cartridge-based video game console, and died earlier this month.
This has inspired a bit of research on my part, as I wasn't born yet and don't know much about the pre-Atari consoles, and didn't entirely understand the difference between the Fairchild Channel F and the Magnavox Odyssey (which someone was WHINING about in the comments of said article as being REALLY the first console).
If I understand right, what it comes down to is that the Odyssey could play multiple games but the code for those games was present in the base hardware and the cards you put in only adjusted the options, setting which subset of features would be made available. That, combined with the picture the user manually attaches to the TV screen, creates the impression of different games while actually being quite limited in what you can do with it.
The Channel F, on the other hand, had programs on cartridges, and thus sufficiently weird people can write new games for it even today.