
If playing online you'd also automatically download any map you don't have from the server.

I'm not sure about Quake 2 but for QuakeWorld you'll get the shareware version of the game which means you'll have the first episode of the singleplayer campaign, a bunch of custom maps included in the nQuake package as well as GPL compatible replacements for the DM series maps. Quake 4 is a free multiplatform game (al. The installers makes it easy to get started with this it downloads the shareware versions plus some other additions such as updated game clients, skins, textures and have a decent default config etc. Quake 4 latest version: Update to the latest version and get new game modes.

Both QuakeWorld and Quake 2 have the nQuake installer and "Quake 2 starter installer" that can be used for multiplayer/online using the Shareware version of the games.
