Capture the Entire Screen:

• Press Command (⌘) + Shift + 3 simultaneously.
• You'll hear a camera shutter sound, and the screenshot will be saved as a file on your desktop by default.

Capture a Selected Portion of the Screen:

• Press Command (⌘) + Shift + 4 simultaneously.
• Your cursor will change to a crosshair.
• Click and drag to select the portion of the screen you want to capture.
• Release the mouse button to take the screenshot.
• Like before, the screenshot will be saved as a file on your desktop.

Capture a Specific Window:

• Press Command (⌘) + Shift + 4 simultaneously.
• Press the Spacebar.
• Your cursor will change to a camera icon.
• Move the camera icon over the window you want to capture (it will be highlighted).
• Click on the window to take the screenshot.
• The screenshot will also be saved as a file on your desktop.