This format is used to create images without compression on Nikon Coolpix cameras. The created RAW files contain electronic data from the camera sensor. It is able to save more data compared with compressed photos. With NRW files you can set the exposure, white balance and other settings while preserving all the details in the image.
This format is used to store background images in uncompressed form in the X Windows System user interface for remote server maintenance. It stores a 'dump' or screenshot of the window or background of the client program. It may include different colors depending on the capabilities of the graphics card that is used to create the XWD file.