For all of you who are like me and can’t seem to remember every single keyboard shortcut here a little short cut of my own.

This is the screenshot short cuts for Mac OSX

• Command-Shift-3: Take a screenshot of the screen, and save it as a file on the desktop
• Command-Shift-4, then select an area: Take a screenshot of an area and save it as a file on the desktop
• Command-Shift-4, then space, then click a window: Take a screenshot of a window and save it as a file on the desktop
• Command-Control-Shift-3: Take a screenshot of the screen, and save it to the clipboard
• Command-Control-Shift-4, then select an area: Take a screenshot of an area and save it to the clipboard
• Command-Control-Shift-4, then space, then click a window: Take a screenshot of a window and save it to the clipboard

In Leopard, the following keys can be held down while selecting an area (via Command-Shift-4 or Command-Control-Shift-4):

• Space, to lock the size of the selected region and instead move it when the mouse moves
• Shift, to resize only one edge of the selected region
• Option, to resize the selected region with its center as the anchor point