Variable may refer to:

• Variable (computer science), a symbolic name associated with a value and whose associated value may be changed

• Variable (mathematics), a symbol that represents a quantity in a mathematical expression, as used in many sciences

Mathematics

• Propositional variable, taking the value true or false in mathematical logic

Random variable, a variable in statistics whose value depends on random events

• Categorical variable, taking one of a finite number of values in a statistical problem, such as the head or tail result of a tossed coin

• Independent and identically distributed random variables, statistically independent and having the same probability distribution

• Fluent (mathematics), a time-varying quantity as coined by Isaac Newton in his early calculus

• State variable, used to describe the mathematical "state" of a dynamical system

• Slack variable, inserted to transform an inequality constraint in an optimization problem into an equality

• Dependent and independent variables, a variable classified according to whether or not it depends for its value on another variable of interest

• Free variables and bound variables, restricted or otherwise to a specified set of values, such as through a logical quantifier

• Complex variable, the argument or value of a function of a complex number in complex analysis

Physical and social sciences

• Variable (research), a logical set of attributes

• Control variable, a measurable entity which is constant (controlled) and unchanged throughout the course of a scientific experiment

• Variable star, a type of astronomical star

Other uses

• "The Variable", an episode of the television series Lost

See also

• Hidden variable (disambiguation)

• Variability (disambiguation)

• Variance (disambiguation)

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