Generally, quantization is the state of being constrained to a set of discrete values, rather than varying continuously.

• In signal processing, quantization is the process of approximating a continuous signal by a set of discrete symbols or integer values.
  • In imaging software, quantization is the process of reducing the number of colors used to represent an image.
  • In music software, quantization is the altering of the times and durations of notes so they fit the beat or subbeat perfectly.
• In physics, quantization is either the taking of discrete rather than continuous values for some physical quantities; or the procedure to construct a quantum theory from its classical limit.