When I buy a game from Steam, I like how I can play it straight from my computer without needing the disc. However, I have a few games that I did not get through Steam, which of course require the disc. I noticed recently that there is an option for me to "add a non-Steam game" to Steam. My question is: what will this do? Will it make it so I can play the game without a disc? If not, is there any way for me to do this using Steam? I don't want to use a disc crack, as I would like to do things legally. Thanks in advance for the help.