OS X Newbie shortcut question I have just moved onto OS X from Windows and am using an early mac pro.

Inside eclipse, when I hover over the toolbar, there are various keyboard shortcuts, (like F11 for 'Run'). 

However, when I press F11 on my keyboard, all it does is making the volume on OS X go down. Am I doing something wrong? This keyboard shortcut is pretty useful so Id rather not lose it.
Go to System Preferences -> Keyboard and check "Use all F1, F2, etc. keys as standard function keys." System Preferences can be found in the Apple menu, or in your Applications folder. Then, make sure that Eclipse still has the F11 shortcut for 'Run' - it might be different on OS X.