In Microsoft Windows, a screenshot of the entire monitor, complete with taskbar, can be copied to the system clipboard by pressing the Prt Sc key. Alternatively, pressing Alt+Prt Sc will copy just the active window to the clipboard. You can then paste the clipboard into a program like MS Paint or Paint.NET using Ctrl+V, and then save it as an image file (for uploading to Wikipedia, for instance).
In Mac OS X, simply prepare your screen to how you want it to look, then hit ⌘ Cmd+⇧ Shift+3 (not the number pad 3) simultaneously. The new image will appear as a PNG on your desktop. Additionally, if you only want to capture part of the screen, you can hit ⌘ Cmd+⇧ Shift+4, click and drag over the part of the screen you would like to capture and release, also saving it as a PNG on your desktop.
This user lives in the great state of Washington. This user does NOT live in Washington State, which is a university. This user does not reside in Washington, D.C., either.
