
To use a keyboard shortcut, or key combination, you press a modifier key with a character key. For example, pressing the Command key (the key with a
 symbol) and the "c" key at the same time copies  whatever is currently 
selected (text, graphics, and so forth) into the  Clipboard. This is 
also known as the Command-C key combination (or  keyboard shortcut).
 symbol) and the "c" key at the same time copies  whatever is currently 
selected (text, graphics, and so forth) into the  Clipboard. This is 
also known as the Command-C key combination (or  keyboard shortcut).A modifier key is a part of many key combinations. A modifier key alters the way other keystrokes or mouse clicks are interpreted by Mac OS X. Modifier keys include: Command, Control, Option, Shift, Caps Lock, and the fn key (if your keyboard has a fn key).
Here are the modifier key symbols you can see in Mac OS X menus:

 (Command key) - On some Apple keyboards, this key also has an Apple logo (
 (Command key) - On some Apple keyboards, this key also has an Apple logo ( )
) (Control key)
 (Control key) (Option key) - "Alt" may also appear on this key
 (Option key) - "Alt" may also appear on this key (Shift key)
 (Shift key) (Caps Lock) - Toggles Caps Lock on or off
 (Caps Lock) - Toggles Caps Lock on or offfn (Function key)
Startup keyboard shortcuts
Press the key or key combination until the expected function occurs/appears (for example, hold Option during startup until Startup Manager appears, or Shift until "Safe Boot" appears). Tip: If a startup function doesn't work and you use a third-party keyboard, connect an Apple keyboard and try again.
See All Key for OS X here







