Once you buy a steam game, you can use it on any computer, provided that the computer can run it. There should be no need to re-buy the mac versions of the same games, though you will need to download the mac versions of the game to your new computer. However, not all games for Windows work on Mac or Linux. That is why your mac specific games are less than your total number of games. There are some workarounds involving getting windows to run on your mac (in virtual machines or something like ).
If you do that, you can install a windows version of steam and play your windows games there, but they are not mac native and may not work as well as you would expect. When you open Steam on the Mac, your game library is by default shown with a filter for games released under the 'SteamPlay' label. Buying games with this label always gives you the Mac version or the Mac and Linux versions for free in addition to the Windows version of the software. You'll see either of these logos on games with SteamPlay: (Windows and Mac support) (Windows, Mac and Linux support) Sometimes a game publisher might release a SteamPlay version of a game separately from the original, Windows only version. In that case, you will need to buy the new version that includes Mac support.
Reference: As for Windows-only games, in addition to trying out the open source Windows compatibility layer, WINE, you could also install Windows on the Mac with Apple’s Boot Camp. This has worked well for me with running games with complex graphics that might not be as optimized when running under Mac OS X. Some games only run on Windows. These games, obviously, will not run on your Mac and do not appear by default in your library.
Explore 19 Mac apps like Steam, all suggested and ranked by the AlternativeTo user. Browse through thousands of free Indie Games ready for you to play. Aug 20, 2012. A windows box, but even so, most games don't support OS X. Even on Steam, the. There are a few options for running those PC games on Macs, of course. I chose Guild Wars: it's a game that has gone free to play lately,.
Unfortunately, this is a technical limitation which generally cannot be worked around by giving Valve more money. WINE, as mentioned in another answer, may give you some success, but in my experience, it is very case-by-case in how well it works. Steam does not make you re-buy games.
(I want to say 'ever,' but I'm not 100% sure there isn't some really weird situation where you could end up buying a game twice). Once you own it, it is attached to your account for good. You do need to download your games again, though. You might be able to copy the steamapps folder from Windows to Mac, but I don't have experience doing that cross-OS.