What is the Mac equivilent of ALT+PrintScreen? I've just started using Delphi to create OSX programs. I'd like to be able to take a screenshot of just the currently active window on the Mac and save it to the clipboard. On Windows you press [Alt] + [PrtScn]. 

What is the equivilent on a Mac?
To take a screenshot of a window press: ⌘ cmd+⇧ shift+4 and then press Spacebar. With this hover the mouse over the window You want to take a screenshot of and press Left mouse/trackpad button.