How to take a screenshot on Mac?

How to take a screenshot of your entire screen

1. Press Shift-Command (⌘)-3.
2. Find the screenshot as a .png file on your desktop.

How to take a screenshot of a window

1. Press Shift-Command-4. The pointer changes to a crosshair.
2. Press the Spacebar. The pointer changes to a camera.
3. Move the camera over a window to highlight it.
4. Click your mouse or trackpad. To cancel, press the Esc (Escape) key before you click.
5. Find the screenshot as a .png file on your desktop.

You can find alternative ways of taking a screenshot on Mac here.