Apple HIG: Keyboard Shortcuts Quick Reference
Chapter: Apple Human Interface Guidelines Section: Keyboard Shortcuts Quick Reference Extract: As you implement keyboard shortcuts in your application, use this table to find: * Which key sequences are reserved by Mac OS X. Users rely on these shortcuts to perform the specified actions no matter which application is currently running (these include shortcuts reserved for accessibility purposes). Do not override these shortcuts. * Which key sequences are recommended for common application tasks. Users expect these shortcuts to mean the same thing from application to application. Provide these shortcuts if your application performs the associated tasks. You should avoid using these shortcuts for other purposes. Link: click here.