MacOS uses keyboard shortcuts to take screenshots.
- A screenshot of the entire screen: Shift+command+3
- A screenshot of part of the screen: Shift+command+4 and make a selection with the mouse of what you would like to capture.
- Capture a window or menu: Shift+command+4 followed by spacebar and then click the desired window.
- For more information about screenshots on MacOS, take a look at the Apple manual.