Instructions for latest OS 

To capture:

• An image of the entire screen, press Command-Shift-3.
• A particular area of the screen, press Command-Shift-4. This will change the shape of the mouse cursor. Drag to select the area of the screen to capture.
• An image of only a certain window, press Command-Shift-4-Caps Lock, then click the mouse pointer in the desired window.

These methods will store the screen image in the root level of the local hard drive as a Simple Text image. If you wish to copy the images to the Clipboard instead, hold down the Control key as you select the part of the screen or window.

Instructions for MacOS 

To capture:

• An image of the entire screen, press Command-Shift-3.
• A particular area of the screen, press Command-Shift-4. This will change the shape of the mouse cursor. Drag to select the area of the screen to capture.
• An image of only a certain window, press Command-Shift-4-Space bar, then click the mouse pointer in the desired window.

An image file will be created on your desktop. Images will be named Picture 1, Picture 2, etc. Images can be copied to the clipboard instead by holding the control key when pressing the mouse button.