Binary means composed of two parts or two pieces. It contrasts with Unary, Ternary, Quaternary, and so on.

Binary may also refer to:

• Binary option, also known as digital option OR all-or-nothing option
• Binary numeral system, a representation for numbers using only two digits (usually, 0 and 1)
• Binary function, a function in mathematics that takes two arguments
• Binary data, composed of something other than human-readable text
• Executable file, a "binary", containing machine code for the computer to execute
• Binary compound, a chemical compound containing two different chemical elements
• Binary explosive, an explosive made of two components that become explosive when mixed.
• Binary (chemical weapon), containing two chemicals that when combined make a toxic agent
• Binary fission, the splitting of a single-celled organism into two daughter cells
• Binary star, a star system with two stars in it
• Binary planet, two planetary bodies of comparable mass orbiting each other
• Binary asteroid, two asteroids orbiting each other
• Binary (novel), a 1972 novel by Michael Crichton (writing as John Lange)
• Binary (comics), a superheroine in the Marvel Universe
• Binary form, a way of structuring a piece of music
• Binary bet, a bet on a proposition which is quoted as a spread bet
• Binary code, the digital representation of text and data.

See also

• Binary prefix, indicating magnitude multipliers in a base-two number system (e.g., kilo-, kibi-, etc.)
• Binary tree, a computer tree data structure in which each node has at most two children
• Binary-coded decimal, a method for encoding for decimal digits in binary sequences
• Finger binary, a system for counting in binary numbers on the fingers of human hands
• Binomial %28disambiguation%29