One of the questions that EIT will ask when troubleshooting a problem on the Mac is if the user has restarted the Mac. This is because there are a number of issues that a simple restart can resolve. For instance, restarting can resolve a problem the Mac is having with a printer or an issue with a particular application. Not only is restarting a good idea to troubleshoot existing issues, it is also a good preventative maintenance practice. Restarting your Mac around once a month can help keep your Mac functioning properly.
To restart your Mac:- On your Mac, choose Apple menu
> Restart. - When troubleshooting an existing issue on the Mac, it's recommended to Quit all open Applications and deselect "Reopen windows when logging back in."