This panel lets you do some frivolous fine-tuning of your mouse, keyboard, and (for laptops) trackpad. It also unlocks Mac OS X's strange and remarkable Full Keyboard Access feature, which lets you control your Mac's menus, windows, dialog boxes, buttons, the Dock, and the toolbar—all from the keyboard. Here's a tour of the Keyboard & Mouse panel's various tabs.
The changes you make are teeny tiny, but can have a cumulatively big impact on your daily typing routine.
Key Repeat Rate, Delay Until Repeat. You're probably too young to remember the antique once known as the typewriter. On some electric versions of this machine, you could hold down the letter X key to type a series of XXXXXXXs—ideal for crossing something out in a contract, for example.
On the Mac, every key behaves this way. Hold down any key long enough, and it starts spitting out repetitions, making it easy to type, for example, "No WAAAAAAAY!" or "You go, girrrrrrrrrl!" These two sliders govern this behavior. On the right: a slider that determines how long you must hold down the key before it starts repeating (to prevent triggering repetitions accidentally, in other words). On the left: a slider that governs how fast each key spits out letters once the spitting has begun.
Use the F1–F12 keys to control software features. On Mac laptops, many of the F-keys on the top row perform laptop-related functions. For example, the F1 andF2 keys adjust the screen brightness, F3, F4, and F5 control the ...