If your Mac keyboard does not respond properly when you try to type something, you may have the "Num Lock" feature enabled on the keyboard. "Num Lock" disables the letter keys on the keyboard and enables the alternate numeric keypad embedded into the keyboard, making it possible to enter numbers using a simulated 10-key keypad on the laptop keyboard. Unlocking the Mac keyboard is a simple and straightforward task.
Locate the "F6" key at the top of the keyboard. The "F6" key is often above the "5" or "6" key on the keyboard.
Locate the "Fn" or "Function" key on the keyboard. The "Fn" or "Function" key is usually in the bottom left corner of the keyboard.
Press and hold the "Fn" or "Function" key and press the "F6" key until the green or orange light on the "F6" key disappears. A green or orange light on the key signals that "Num Lock" is active; no light signals that "Num Lock" is inactive.
If you're unable to unlock your keyboard with these steps, the keyboard may be faulty.