Posted by Mike Dailly on 13 May 2013
One of our most requested items has been to put the documentation online so developers can reference it easily, and up until now we've put it off, mainly because we don't want it to get "stale". GameMaker: Studio is an evolving platform, and as such commands are added, changed or even removed all the time, so in order to do this properly, it had to be done as part of our internal build procedure. This would mean that when a new version is released, the documentation would be automatically updated, and uploaded.
We are pleased to announce, this has now been done, and the documentation is available online. You can now reach it at the easy to remember URL: docs.yoyogames.com