Steam has started supporting and distributing Mac games a couple of months ago. You can use the Advanced Search to filter by OS. At the time I am writing there a 138 games and 18 DLC
for Mac listed there.
On 19 June 2010, Appstorm.net wrote an article about 50 Games for Mac.
Wikipedia has a long list as well.
Pay attention that not all games run on all Mac models. Check the requirements before buying them.
Most multi-platform games share a large amount of data between platforms, even though the actual executable is different.
Let's look at Half-Life 2 and other Source games. They have lots of *.gcf
files inside the Steam\steamapps
folder. Those files contain all the multimedia assets (levels, audio, textures, 3D models...), and such data is identical to both Mac and Win versions. Thus, you can safely copy such files from your Mac Steam to your Windows Steam, saving you a few gigabytes of downloads. Then, the Windows Steam will still download Windows-only files, but they are quite small, maybe less then 100MB.
It also works the other way around: copying files from Windows to Mac.
What I've described should also work on most steamplay titles, that are available on Steam for Mac and Windows. (but you might need to copy files from subdirectories inside Steam\steamapps\common
)
However, if you want to download a Windows-only game, then you might need to run the Windows version of Steam. You may achieve that using one of the many virtualization options (VMware, VirtualBox, Parallels), or even try your luck running Steam under Wine (but that might be too buggy).
Best Answer
In the general case, you normally can't expect to go to your favorite game shop, pick up a PC game, take it home, and expect to be able to put the game on your Mac and have it run. However, it is possible to play PC games on a Mac. When attempting to play a Windows game on a Mac OS-based machine, you have several options, each with its drawbacks and strengths.
Please note: This is intended as general advice to a non-technical audience. This is not indented to be a "catch-all" answer to "how do I overcome game X's difficulties when running under solution Y." The existence of this answer does not mark every other MacOS gaming question on this topic as a duplicate. It is further not meant to be a full and complete overview of WINE/Virtual Machines/dual booting/etc. The intent is to generally summarize the solutions to allow people to choose a direction to invest further effort.
Get the Mac Port
If it exists, getting the Mac port or playing it natively on your Mac is almost always the best way to play any game on a Mac. With the advent of things like SteamPlay and the rise of independent game houses, more and more games are coming out for the Mac. Don't assume that the game is Windows-only until you've done the research. More and more games are now showing up in browsers, which can also sometimes make them platform independent. Whenever you can, invest time in researching the Mac version of a game, as playing it typically produces the best experience.
Pros
Cons
Virtual Machine
With desktop virtual machine software, you can run a copy of Windows as a "program" under Mac OS. Several software packages exist, such as VirtualBox, Parallels, and VMWare Fusion. Once you've installed the virtual machine software, you can follow a simple wizard to create a file on your hard drive to hold your Windows installation and applications, and then the system will walk you through setting up Windows from the install media.
Pros
Cons
Dual Boot
With Apple's BootCamp software, you can install Windows into a separate part of your Mac's hard drive, and then you can choose to start either Windows or Mac OS on your Mac when you start it up. Apple provides technical manuals for properly installing BootCamp on your Mac, which are easy to follow and thorough.
Pros
Cons
Emulation
Virtual machines emulate an entire PC, but oftentimes this solution is overkill. Emulators (and similar programs) only fake part of the device or OS in question, which can yield better performance with less overhead. Many different types/classes of emulators exist that emulate a wide variety of platforms and systems, for example:
Pros
Cons
Cloud Gaming
A fairly recent development is "cloud gaming" where the game's video is "streamed" to your computer in a fashion similar to how Netflix works, as opposed to your computer's OS and hardware rendering the video data locally. OnLive, one prominent player in this space, offers a wide library of games to choose from and supports playing games on most modern Macs.
Pros
Cons