1. Click on the Apple menu, hold the Option key and select System Information....
   

The computer name will be at the bottom of the System Report screen, next to a miniature icon of the computer being used.

The computer name is on a light-blue background at the bottom left of the window. See below:

Finding the Serial Number 

If your Mac does not boot or you cannot sign into the machine, you can instead provide your IT support staff with the serial number of your Mac.

Note: for information on where to look for your ipad please click here

iMacs have the serial number located on the bottom of the foot of the machine. You can carefully lay it back to see the serial number. 

Instructions to find your serial number can be found at the fi: https://support.apple.com/en-us/HT204308