You can use the Snipping Tool on Windows to grab a screenshot.

 1) Click on the Start Menu

 2) Type "snip" in the Search programs and files field

 3) Click on "Snipping Tool"

 4) You can then select a region to grab a screenshot

 

You can use the keyboard short cut combination"CMD+Shift+3" on MAC to grab a screenshot.

 

For Chromebook, you can use the keyboard short cut combination "Control+Switch window" or "Control+F5" on non-Chromebook keyboards.