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 percepted 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 <math>\aleph_0</math>. (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.

(It is not the same thing as discreet[?].)