Binary is a numerical system that uses only two digits, typically 0 and 1, to represent numbers, characters, and other data. It is the foundation of all digital electronics and computing systems, as it allows for the storage and manipulation of information using electronic circuits that can be in one of two states, on or off. In binary, each digit represents a power of 2, with the rightmost digit representing 2^0 (1), the next digit representing 2^1 (2), and so on. Binary is often used in computer programming, networking, and other fields related to information technology.