Can You Add a Regular Keyboard to the iMac?by Aubrey Kerr
The iMac is shipped with a low-profile wireless keyboard, but you can add a wired USB keyboard or a larger wireless Bluetooth keyboard if you prefer a larger typing surface. All iMacs run Apple's OS X operating system, so you can add a new keyboard in the same way no matter which version of OS X is installed on your iMac.
Not all keyboards are Mac-compatible. Check the keyboard's system requirements or the manufacturer's website for Mac compatibility before you purchase a new keyboard. Sometimes the factory-set function keys are incompatible while the typing function of the keyboard works fine. If you want to use a keyboard you have on hand, plug it into a USB port on your iMac and test it out.
The iMac will recognize most ANSI, JIS and ISO keyboards. ANSI is the standard keyboard type used in North America. ISO keyboards are used mainly in Europe and JIS keyboards are used in Japan. You can specify any one of these keyboard types by going to System Preferences and selecting Keyboard & Mouse followed by Change Keyboard Type.
When you plug a USB keyboard into an iMac the Keyboard Setup Assistant will open so you can set your keyboard preferences. This includes turning the function keys on or off. If the keyboard isn't automatically recognized, select System Preferences in the dock and click Keyboard & Mouse. From there you can click Change Keyboard Type to launch the Setup Assistant.
To connect a different wireless keyboard to the iMac, make sure the keyboard has fresh batteries installed and then turn the keyboard's power on. Open System Preferences followed by View and then Bluetooth on your iMac. Make sure Bluetooth is enabled and the iMac will automatically pair with the keyboard. You may have to click "Accept" to activate the connection. Check the keyboard signal strength by opening System Preferences, Keyboard & Mouse and then Bluetooth.