They label some files "PC only" because they don't know about MaConverter, although .exe files (apps) are always "PC only". They label other files "PC/Mac" because it's the default setting for freestuff. It's almost always the correct setting, thanks to MaConverter. Most of them are PC files. They label files "Mac only" if they're .sit files. So those can sometimes be used on a PC with Expander, unless they're Mac apps.