The ANSI Art tool is used for rendering ANSI art files (usually with .ANS extension). The tool parses this file and converts the characters into their original old-skool MS-DOS equivalent font. The modern ASCII set isn’t quite the same, so this program redraws each character from a font map.
ANSI art is a form of computer art that flourished in the mid 90s. ANSI art was composed by colorizing sequences of characters and blocks drawn in the built-in system font, which made it easy to transmit across telephone wires. As a result, ANSI art was especially popular on Bulletin Board Systems (BBSes).