To capture a window or menu, press and hold - Shift, Command, 4, and Space bar. You can even edit it by clicking on the thumbnail. The screenshot will be saved to your Macbook. Now drag the crosshair to select the area of the screen that you want to capture and release your mouse or trackpad button. If you wish to capture a portion of the screen, press and hold Shift, Command, and 4 together. A thumbnail will appear in the corner of your screen, you can click it to edit the screenshot or save it on your desktop. To grab the entire screen, you have to press and hold three keys together- Shift, Command, and 3. With this trick you can capture the entire screen, a window, or just a portion of the screen easily.
