I’d say most of the people who clicked this have no idea what it is.
Traditionally with buying a videogame, it’s going into EB Games or whatever, throwing some money on the counter and a game box. The clerk gives you the game and you walk out of there with a reciept and a bag. However, there are some problems with that. Namely, a huge one. The chain Gamestop has managed to make huge profit simply by agressively pushing used games and hardware instead of the new ones. This allows them to make huge amounts of cashgolddollars because they’re basically selling the used games at maybe twice what they paid their consumers for returning the games. This allowed them to order as little new merchandise from suppliers as possible, to cut costs.

GameStop CEO's new house.
Digital distribution will change that. GameStop will not be able to make that much money anymore, because of game publishers like Valve (And the Steam content delivery system). Nowadays, if you want to buy a PC game, you just go on Steam and download it (For a price, of course). It’s much faster than having to go to a store, not to mention you don’t even have to leave your house (Couch potatoes rejoice!).

Digital distribution is great, but it’s not just Steam. One type you may know very well would be iTunes. You’re buying music electronically instead of having to go to a store to get a CD, and that’s pretty convenient. That’s another type of digital distribution.
Of course, consoles have their own digital distribution too.

WiiWare is for the Wii. (Duh). Lots of retro games from the NES, SNES and N64 days. It’s pretty great.

the PSN isn’t bad either. Lots of great games, not to mention tons of downloadable content for the games you’ve already bought (Content which enhances the game, eg secret characters). Lots of fun games on here like Noby Noby Boy. Some retro games on here too, but they’re great ones (Tekken 5: Dark Resurrection
)

And, of course, the Xbox. Tons of downloadable content too, lots of extra maps and whatnot. Some great games too (Braid…) and…yeah!
What do you think about downloadable content? Will it help the game industry? How?