Discrete

From Wikipedia, the free encyclopedia

The word discrete comes from the 15th Century 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 topology, a branch of mathematics, a discrete space is a topological space in which all sets are open, and a discrete set is a set of isolated points.
• In discrete mathematics, without notion of continuity, a discrete set is a countable set; this concept is also important for combinatorics, probability theory, and statistical theory.
• In statistics a discrete random variable defines a particular type of variable in a discrete probability distribution (in contrast to a continuous random variable).
• In discrete mathematics and in theoretical computer science, the abstract world is usually modeled as a discrete space with discrete time.
• In electrical engineering and electronic engineering, discrete means having separate electronic components, such as individual resistors and inductors. This is the opposite of integrated circuitry.
• In audio engineering, discrete means having separate and independent channels of audio, as opposed to matrixed stereo or quadrophonic, or other multi-channel sound.
• A discrete signal in information theory and signal processing
• In music, a discrete pitch is one with a steady frequency, rather than an indiscrete gliding, glissando or portamento, pitch.
• In project management, discrete effort is any activity with a pre-defined state of completion; the opposite of discrete effort is continuous, operational or ongoing effort.

Discrete is not the same thing as discreet.