Binary (or base-2) a numeric system that only uses two digits — 0 and 1. Computers operate in binary, meaning they store data and perform calculations using only zeros and ones. A single binary digit can only represent True (1) or False (0) in boolean logic.1. Binary is a base-2 number system invented by Gottfried Leibniz that is made up of only two numbers: 0 and 1. This number system is the basis for all binary code, which is used to write data such as the computer processor instructions used every day.