Quote Originally Posted by lescha View Post
Doesn't DRM simply mean getting a query and sending a reply every certain period of time, doesn't it? Verification stuff.
DRM is a broad term for "digital rights management" (or "digital restriction management", as some, like me, prefer to call it), a set of technical measures to control the usage done of a piece of digital content (game, e-book, music, movie, ...) in theory to prevent illegal copying, but sometimes for other purpose too, like planting a "time bomb" in a beta, to be sure people don't keep using the beta once the final version is released, or doing region control on DVDs.

Some DRM measures involve calling a server and checking its reply, some involve cryptography (like CSS, the DRM that is part of most DVDs). It can be said that the old-school "enter the 3rd word of the 12th page of the manual" was a primitive form of DRM.

More generally, in the context of games, a "DRM-free" version usually means a stand-alone copy that you can get using a standard protocol (such as HTTP or FTP) and can then install on any computer you wish, without that version ever "calling home" nor doing any specific checks, ie, it doesn't contain any "digital restriction measures", if it doesn't run it's just because it can't (insufficient hardware, missing libraries or driver, incompatible system, ...).