Stores a screenshot, or "screen dump," of a window or background in the X Windows system; created by the xwd client process and saved as an uncompressed bitmap.

Different XWD files may contain different amounts of colors depending on video card of the machine the image was captured with; because they are uncompressed, XWD files may be very large in size.

Important: X10 and X11 use slightly different XWD formats, so some files may not be compatible with certain XWD viewers.