Common questions about your Mac
How do I get support for my iMac? Go to iMac Support.
I’m new to Mac. Are there tips for PC users? Yes! See the Apple Support article Mac tips for Windows switchers. Check out the Mac Basics Quick Tour. You might also be interested in Keyboard shortcuts on your Mac.
How do I take a screenshot on my Mac? Press Command-Shift-3 to take a screenshot of the entire screen. Press Command-Shift-4 to take a screenshot of a selected area of the screen. To learn more, see Take a screenshot on your Mac.
Where is my serial number? Choose Apple menu 
> About This Mac. The serial number is the last item in the list. You can find the serial number on the bottom of the iMac stand.
Ask Siri. Say something like: “What’s my computer’s serial number?”
How do I know which model of iMac I have? See the Apple Support article Identify your iMac model. You can also choose Apple menu > About This Mac to view the model information.
How can I find the documentation for my iMac? To find the Essentials guide, choose Apple menu > About This Mac, click the Support tab, then click User Manual. From the Support tab, you can also click “macOS Help” to open the user guide for the operating system. For older Mac models, see Browse manuals by product.
How do I get help for an app? When you’re using the app, click the Help menu in the menu bar at the top of the screen.
Where is the safety information for my iMac? See Important safety information for your Mac.
How do I find the technical specifications? Go to iMac Tech Specs, or choose Apple menu > About This Mac and click the buttons at the top.
Ask Siri. Ask Siri for information about your Mac. Say something like:
“How fast is my Mac?”
“How much memory does my Mac have?”
“How much free space do I have on my Mac?”
“How much iCloud storage do I have left?”
How do I check my disk for problems? Use Disk Utility. See Repair a storage device in Disk Utility on Mac in the Disk Utility User Guide.
What should I do before selling or trading in my Mac? Back up your data, then restore your Mac to factory settings. See What to do before you sell, give away, or trade in your Mac.