Screenshot
A
screenshot,
screen dump, or
screen capture is an
image taken by the
computer to record the visible items on the
monitor or another visual output device, usually this is a digital image taken by the host operating system or software running on the computer device but it can also mean when a capture is made by an external device such as a
camera or something intercepting the video output of the computer.
Screenshots, screen dumps or screen captures can be used to demonstrate a program, a particular problem a user might be having or generally when computer output needs to be shown to others or archived, the most common of the three is a screenshot which commonly means outputting the entire screen in a common format such as
PNG or
JPEG, a screen dump is when the display system
dumps what it is using internally upon request, such as
XWD X Window Dump image data in the case of
X11 or
PDF in the case of
Mac OS X. Finally a screen capture commonly means to capture the screen over an extended period of time to form a
Video file.
Taking screenshots
\nThere are numerous ways to take a screenshot on many operating systems, and applications. This article attempts to cover the ones that use standard software on each platform to achieve the task.
Microsoft Windows
\nIn Microsoft Windows a screenshot of the entire monitor, complete with taskbar, can be copied to the system clipboard by pressing the Print Screen button. Alternatively, pressing ALT + Print Screen will copy just the active window to the clipboard.
This method does not work with hardware overlays.
Mac OS X
\nTo save an image of the entire screen in Mac OS X pressing Command + Shift + 3 saves a PDF file on the desktop ( ~/Desktop/ ) containing a PDF Dump of the screen.
To take a picture of part of the screen pressing Command + Shift + 4 and then select the area to be captured.
To take a picture of a window or menu, press the space bar after Command + Shift + 4. By default, the captures are stored in PDF on the desktop. To copy the captures to the clipboard, press the control key along with the other keys.
X Window System
\nSince the X Window System itself is not a desktop environment and only includes a very basic set of programs it is not common for the xwd(1) command to be used, most people use other bundled utilities to achieve the task.
xwd
\nOn systems running the X Window System the standard utility to dump an image of an X Window is xwd(1), xwd produces XWD X Window Dump image data. It can be invoked in the following way:\n xwd -root -out root.xwd\nxwd can also be used to dump a single window if provided with the -id option followed by the corresponding window id, for further info see man 1 xwd [1]. When run remotely, wxd is useful for taking screen shots of modal menus in action.
ImageMagick
\nAlternatively if you have ImageMagick installed the following command can be used to import the root window and everything above to a PNG image file called root_window.png, it uses the convert(1) utility, you can take a screenshot of the entire contents of the screen with this command:\n import -window root root_window.png\nAlternatively you can use the import command without any arguments, you will then be presented with a cursor with which you can click on a window and the image generated will contain a image of that window only.\n import root_window.png
KDE and GNOME
\nIn the K Desktop Environment, the built-in program KSnapshot is the default screen grabbing utility. GNOME users can also use the Screen-Shooter applet, choose "Take Screenshot" from the actions menu or press 'print screen'.
The GIMP
\nThe GIMP can also be used to take screenshots on any platform it is available on, simply navigate File->Acquire->Screenshot on the toolbox menu to capture either the current screen or choose timed mode.
See also
\n*Thumbnail\n*Thumbshot
\nA thumbnailed screenshot of the Wikipedia website, taken on Debian GNU/Linux running the X Window system\n