Capturing what is on your computer's screen is called a screenshot. It is ordinarily spared within the Desktop envelope unless you've got customized the setting.
To get a full screen on a Mac, press the 'Command', 'Shift', and '3' keys at the same time. This ought to cause the show to glint or alter quickly, and the screenshot will be spared to the Mac desktop.
To capture portion of the screen on a Mac, press the 'Command',
'Shift', and '5' keys together.
This will bring up the screen-capture window, where you'll utilize the crosshair pointer to choose an range.