This file format is used as a canvas (background) in a variety of image editing software in order to set the main color of the image. It is used to fill the canvas with one solid color. It belongs to the group of 'pseudo-image' file formats. It can be used for the fill color, which is chosen from the selected area in a particular image.
This is the display format associated with the broadcast of slow-scan television. This legacy format was used to transmit a static image given limited bandwidth through the use of specialized software.