Yes. The fonts included with OS X are licensed for your use as you see fit.
As most of the fonts are from other vendors, some may have specific restrictions. From the Snow Leopard license agreement:
D. Fonts. Subject to the terms and conditions of this License, you may use the fonts included with the Apple Software to display and print content while running the Apple Software; however, you may only embed fonts in content if that is permitted by the embedding restrictions accompanying the font in question. These embedding restrictions can be found in the Font Book/Preview/Show Font Info panel.
Translation. A font may not allow any embedding at all (such as in a PDF), which means you can really only use it on your computer and to print items directly from your computer. A font may otherwise require only subset embedding, which is normal. If there are no restrictions noted in Font Book, then you can use it any way you want.
oh thanks for your answer. so as long there is no restriction on the we can use them for our brand logo, or brand other comapny, or design for commercial, is'nt it?
ok how about this example: about STHeiti font detail (i copy it from font book). is it ok for commercial??
STHeiti, 18 pt.
PostScript name STHeiti
Full name STHeiti
Language Afrikaans, Albanian, Basque, Belarusian, Bulgarian, Catalan, Chinese, Chinese (Simplified Han), Cornish, Croatian, Czech, Danish, Dutch, English, Esperanto, Estonian, Faroese, Finnish, French, Galician, German, Greek, Hungarian, Icelandic, Indonesian, Irish, Italian, Japanese, Kalaallisut, Latvian, Lithuanian, Macedonian, Malay, Maltese, Manx, Norwegian Bokmål, Norwegian Nynorsk, Oromo, Polish, Portuguese, Russian, Serbian, Sichuan Yi, Slovak, Slovenian, Somali, Spanish, Swahili, Swedish, Swiss German, Turkish, Welsh, Zulu
Unique name STHeiti; 6.1d2e1; 2008-11-18
Copyright Copyright (c) 2002, Changzhou SinoType Technology Co., Ltd. All rights reserved.
Trademark STHeiti and SinoType are trademarks of Changzhou SinoType Technology Co., Ltd.
Copy protected No
Glyph count 32,493
That's a good example. All of the main points at the bottom:
Enabled - Yes : Simply means it's active on your system and ready to be used in any application.
Duplicate - No : You're not allowed to distribute copies of the font, free or otherwise.
Copy protected - No : Self explanatory.
Embeddable - Yes : You can legally embed the font in documents you distribute. Which would generally mean a PDF.
You are not the copyright holder, so no, you cannot sell it, or even include the font itself free in a promotional giveaway.
What many prepress, press shops do to avoid the hassle of all work having to be turned in as PDF, or some other form of document where the font is embedded, they either already have the same fonts, or purchase entire font folios. Then you send them any fonts as is. They already have it themselves, so you're not giving them anything "free", or otherwise against the font's license.