# Discrete

The word**discrete**comes from the latin word

*discretus*which means

*separate*. It is used with different meanings in different contexts:

- In perception a discrete entity is something that can be perceived individually and not as connected to, or part of something else.
- In mathematics a discrete set is a countable or countably infinite, with a cardinality less than or equal to (See Aleph). (Including integers.) Mathematical study of discrete sets is the area of inquiry for discrete mathematics, but also important for combinatorics, probability theory and statistical theory.
- In mathematics, a discrete space is a topological space in which all sets are open.
- In electrical engineering, discrete means having separate electronic components, such as individual resistors and inductors — the opposite of integrated circuitry.

- In audio engineering, discrete means having separate and independent channels of audio, as opposed to matrixeded stereo or quadrophonic, or other multi-channel sound.
- In reference to signals, dynamic systems, or control theory,
**discrete**often means the same thing as digital.

*not*the same thing as .