Apple computers run Mac operating system, which is a UNIX system. Though most users interact with their Mac only through the Graphical User Interface, they can also use an included application known as Terminal to access the command line. It lets you send commands to your Mac by typing text instead of using your mouse with the user interface. Using this terminal, you can use the Unix shell on your Mac to troubleshoot system problems and set shortcuts and preferences like the file format of screenshots or the viewing options for hidden files on your hard drive. There are times when troublesome folders and files may not get deleted using the standard method of moving them to the trash and then emptying the trash. When it happens, you can delete files and folders using the Terminal window. However those who are not familiar with UNIX style environments should be cautious when using Terminal because incorrect commands or improper alterations of the command line can result in severe computer problems.
How to Open Terminal on Mac?