Should you shut your PC or Mac down every night? If your computer does absolutely nothing while you sleep (downloading, converting, backing up, etc), then there really is no reason to keep it on. Many people say turning it off and on will damage your computer, but this is a myth. There is no harm in turning your computer on and off unless you do it 10 times a day.
Shutting down a computer will increase the life of the computer because your components will get less wear and tear. When the computer is on, everything is getting power and the temperature of the memory chips, graphics card, and other parts are higher than if the computer were off. Also, if your computer has a traditional spinning hard drive, shutting down will reduce the total overall spinning of the drive and extend its life. However, since it takes some time for a drive to get up to normal spinning speed, forcing it to stop and then start again and again can also cause more wear on the drive. If you turn off your computer once a day or a few times in a week, you’ll be just fine. However, if you turn it on and off several times a day, it could cause your hard drive’s life to be shortened instead of extended. For an SSD (solid state drive), this is not as much of an issue. You can turn off and on as much as you like.
Shutting down and rebooting either every day or once or twice a week can also help reset the operating system and make it run smoother. Windows and Mac OS X both start to have issues after a few days either with memory or something else and restarting always helps improve the responsiveness of the system.