isr.co.ro : glossary bit (binary digit) a single item of information representing two possible values -- such as 1 or 0, yes or no, light or dark, or on or off. Strings of these binary digits can be used to represent more complex values, such as letters, words, colors, or larger numbers. Because circuits designed to work with binary digits are much easier to build than ones that work directly with complex values, virtually all modern computers work on the binary system. According to the instructions in the computer's programs, the bit strings are interpreted as characters, numbers, logical values, or instructions.