My friend has his computer plugged into a switched power outlet. At the end of the day he simply turns the switch off. Thi seems wrong. Is he harming his computer by doing this?
DO NOT just pull the plug. Computers should not have the power just turned off. It may not have saved information. Many programs do extra things when they are shut down.
You should always do a software shutdown of your computer. This applies to your Mac or PC. I even shutdown my programs first although most programs will be shutdown properly by the operating system.
On the Mac click the Apple icon and select Shutdown. On the PC click the Windows icon, and select shutdown. Wait until it complete the shutdown and then you can turn the power off.
If you have a battery UPS and it has a cable connected to the computer, the UPS will notify the computer to do a nice shutdown before the battery power runs out. Do a controlled shutdown and buy a UPS for your computer.