Unit

The word unit means any of several things:

• Unit of measurement or physical unit, a fundamental quantity of measurement in science or engineering.
• Units (computer program), a popular program that does unit conversion.
• Functional unit, a component of a computer system such as the CPU.
• Unit of action, a discrete piece of action (or beat) in a theatrical presentation.
• Multiple unit, a passenger train whose carriages have their own motors.
• United Nations Intelligence Taskforce, a fictional entity in the Doctor Who television series.
• Unit, a rock and roll album by the Australian band Regurgitator.
• Unit of alcohol, 10 millilitres of pure ethanol in the UK.
• In currency, a unit of money (a monetary unit).
• In a 19-inch rack a rack unit is a standard height of 1.75 inches.

• In mathematics:
  • Unit vector, a vector with length 1.
  • Unit circle, the circle with radius 1 centered at the origin.
  • Unit interval, the interval of all real numbers between 0 and 1.
  • Imaginary unit, i, whose square is -1.
  • Root of unity, a complex number, a power of which is 1.
  • Unit (ring theory), an element that is invertible with respect to ring multiplication.
  • In category theory, there is a natural transformation called the unit from the identity functor to the composition of two adjoint functors, q.v.

• Group regarded as a distinct entity within a larger group such as in Law & Order: Special Victims Unit or Wikipedia's Counter Vandalism Unit
  • Military units, including:
    • Unit 101, an Israeli special operations unit.
    • Unit 731, a secret unit of the Japanese army.