Mac owners, help please
It really depends on what you mean by "best".
Hiarcs is godlike in its strength but so is nearly every program these days.
Shredder is also close to unbeatable by mortal means.
You can also install Windows through either a shared drive/partition (like VMWare or Parrells) and run all the standard Chess applications in this environment.

You do know that Macs get viruses and spyware as well right? There was a pretty nasty rootkit that came out last year which is still a problem.

You do know that Macs get viruses and spyware as well right? There was a pretty nasty rootkit that came out last year which is still a problem.
It looks like it is already too late to save him, the cult has drawn him in too far.
If you only use the Windows partition for programs and not e-mail/web surfing I think you are pretty safe. A I run this at work and have not had a problem as I do not use the web in this partition but use Safari on the Apple partition to surf the web.
If you are looking for a simple "play-against-the computer" option --- there is the Chess application built right into OSX on every Mac.

Nothing flashy --- its a a simple "play-against-the computer" application.
Here are some details from the Apple site:
Challenge yourself to a game.
With Chess in Mac OS X, you can play against your Mac or another person, or watch your Mac play against itself. Customize your chess board and pieces by choosing from a variety of styles. You can use your voice to control the pieces and even have each move spoken out loud.
More details here:
http://en.wikipedia.org/wiki/Chess_%28application%29

i have both, a mac and pc and there are almost NO GOOD chess programs for the pc...use boot camp instead or vmware fusion and run a pc app like Chess Assistant...
Bootcamp is a free (unlike VMWare/parrells which cost about $70 I think) which allows you to run Windows on a mac
Bootcamp means you can not use the Mac O/S at the same time --also requires Windows installation and basically you are running a full Windows machine on a Mac computer and need to turn off/on the computer to switch O/S
I am swtching from a Dell xp laptop to a MacBook Pro. I enjoy my iPad with no worries of spyware or viruses. I look forward to playing chess on a Mac and surfing the net with no worries. Could you tell me the best chess software for a Mac? Stwils