*This post continues our Computer Systems History series.*

A **binary system** is actually an astronomical term referring to two objects in space (usually stars, but also planets, galaxies, or asteroids) which are so close that their gravitational interaction causes them to orbit about a common center of mass. Some definitions require that this center of mass is not located within the interior of either object. A *multiple system* is like a binary system but consists of three or more objects.

A **binary code** is a way of representing text or computer processor instructions by the use of the binary number system’s two-binary digits 0 and 1. This is accomplished by assigning a bit string to each particular symbol or instruction. A binary string of eight binary digits (bits) can represent any of 256 possible values. It can correspond to a variety of different symbols, letters or instructions.

In computing and telecommunication, binary codes are used for any of a variety of methods of encoding data, such as character strings, into bit strings. There are many character sets and many character encodings for them. A bit string, interpreted as a binary number, can be translated into a decimal number. For example, the lowercase “a” as represented by the bit string 01100001, can also be represented as the decimal number 97.

Binary numbers were first described in Chandashutram written by Pingala in 100 BC. Pingala is the traditional name of the author of the Chandaḥśāstra, the earliest known Sanskrit treatise on prosody. The Chandaḥśāstra presents the first known description of a **binary numeral system** in connection with the systematic enumeration of meters with fixed patterns of short and long syllables.

The discussion of the combinatorics of meter corresponds to the** binomial theorem**. Halāyudha’s commentary includes a presentation of the Pascal’s triangle Pingala’s work also contains the Fibonacci number.^{ }Use of zero is sometimes mistakenly ascribed to Pingala due to his discussion of binary numbers, usually represented using 0 and 1 in modern discussion, while Pingala used short and long syllables.

As Pingala’s system ranks binary patterns starting at one (four short syllables—binary “0000”—is the first pattern), the nth pattern corresponds to the binary representation of n-1, written backwards.

Later in 1847, another mathematician and philosopher George Boole published a paper in 1847 called “*The Mathematical Analysis of Logic*” that describes an algebraic system of logic, now known as Boolean algebra. Boole’s system was based on binary, a yes-no, on-off approach that consisted the three most basic operations: AND, OR, and NOT. We all know those!

#### Forms of Binary Code:

- Braiile
- Ba Gua
- Ifá Divination

Besides computers, there are many things that use binary codes including CDs.