Computer pictographs are visual representations of information used to communicate ideas and concepts. They include CAVE, glyph, SYMBOL, ICON, and HAL, which are all four to six letter words. CAVE is a prehistoric drawing found on the walls of caves, glyphs are symbols used in ancient writing systems, symbols are abstract representations of an idea, icons are small images used to represent a program or file, and HAL is a computer program from the movie 2001: A Space Odyssey.