For those who do not know then you explain the different methods of taking screen shots from Snow Leopard. There are different methods:

• Program Snapshot (included in Snow Leopard and Leopard, no need to install anything).
• Keyboard Shortcuts

Snapshot
It is a program that, as discussed above, is installed by default with Leopard and Snow Leopard.

Once opened, go to your Capture menu where we can observe the following:

• Selection
• Window
• Screen
• Timed Screen

Each has its keyboard shortcut, but importantly, we must be with snapshot as active program to work the following keyboard shortcuts:

• Command-Shift-A allows us to use the selection tool
• Command-Shift-W allows us to use the tool to capture Windows
• Command-Z allows us to capture a screen
• Command-Shift-Z allows us to capture a screen timer

Keyboard Shortcuts
There are two ways, depending on whether you want to copy the image to the clipboard or save to your desktop.

• Ctrl-Shift-Command-3, saves the capture made it to the clipboard.
• Shift-Command-3, saves the capture made the whole screen on the desktop.

I hope to serve you for help!