iMac
Intel-based iMac (Mid 2007) and later: How to find the serial number
Learn how to find the serial number of your aluminum Intel-based iMac computer from mid 2007 or later.

How to replace the Apple Remote battery
This article explains how to replace the battery in the Apple Remote Control.

iMac (27-inch, Late 2013): Distorted or black screen when waking from AirPlay Mirroring
When waking from sleep with a iMac (27-inch, Late 2013) computer using AirPlay Mirroring to an available AirPlay device on the network, you may see video distortion or a black screen. With the black screen, you can redraw the desktop … Continue reading
Using Apple Hardware Test
Apple Hardware Test (AHT) contains a suite of diagnostics that will test the hardware of your computer. It’s a great way to rule out a hardware issue when troubleshooting your computer.
iMac (Mid 2012 and later): Noise reduction option is always on
Your iMac (Mid 2012 or later) computer doesn’t have a “Use ambient noise reduction” option visible in System Preferences > Sound for the internal microphone.
Mac mini (Late 2012 and later), iMac (Late 2012 and later): About Fusion Drive
Fusion Drive is a new storage option for Mac mini (Late 2012 and later) and iMac (Late 2012 and later) computers that combines the performance of Flash storage with the capacity of a hard drive.

Learn about the fans in your Mac
Learn more about the control system in your Mac that monitors internal temperatures and delivers airflow to critical components by adjusting fan speed based on feedback from sensors inside the computer.
Bluetooth: How to set up your Apple Wireless Mouse or Magic Trackpad using setup assistant
Learn how to set up your Apple Wireless Mouse or Magic Trackpad if no USB mouse is available during the setup assistant.

iMac (Mid 2011): External features, ports, and connectors
Learn about the external features, ports, and connectors on the iMac (Mid 2011) computers. All ports and connectors described in this document are located on the Input/Output (I/O) panel on the bottom-right side on the back of the computer.