This is a format created in the Acorn Draw program, intended for image visualization by using vector lines. It’s used for storing information in the publishing business (brochures, logotypes, etc.). The main advantage is it’s high quality source images when printing. It’s been in use since 1980.
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.