Capture screenshots on Mac screenshot under Mac

In system settings-keyboard shortcut, you can see the shortcut keys.

Select the options under screenshots to implement the keyboard shortcut.

1) command-shift-3: capture and save the entire screen to the desktop.
2) command-shift-control-3: capture the entire screen and save it to the clipboard (Clipboard). You can directly paste command + V into software such as Photoshop for editing.
3) command-shift-4: Take a part of the screen and save it to the desktop. After you press this key combination, the cursor changes to a cross. You can drag it to select the shooting area.
4) command-shift-control-4: Take a part of the screen and save it to the clipboard.
5) command-shift-4 then press the Space key: Then the cursor will change to a camera icon, click to take the current window, menu, dock, and icon, etc, just move the camera icon to a different area (the valid area is displayed as light blue) and click.
6) command-shift-control-4 then press space: Save the snapshot of the selected window or other areas to the clipboard.

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Also, you can use snap softwares like 'littlesnapper' in Mac.

Using littlesnapper, You can snap screenshots and edit them