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could you guys PLEASE search before posting?!
There have already been half a dozen posts regarding the apple font

its myriad pro, and searching would have saved you a ****load of time.
 
Before the new iMac, they used Apple Garamond (also known as Garamond Narrow) Light. (looks to be about -25) Sometimes Helvetica was put to good use.

After that, they started to move to the Myriad Pro font. Now they use Myriad Pro entirely.

In the system font, I believe it's Lucida Grande.

Myriad Pro: http://store.adobe.com/type/browser/P/P_1706.jhtml;store
Apple Garamond: http://store.adobe.com/type/browser/P/P_1061.jhtml;store

If you have Jaguar or earlier, this is where you can get the exact one.
http://www.osxfaq.com/dailytips/12-2002/12-02.ws

/too lazy to do HTML right now
 
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