**Order theory** is a branch of mathematics which investigates our intuitive notion of order using binary relations. It provides a formal framework for describing statements such as "this is less than that" or "this precedes that". This article introduces the field and provides basic definitions. A list of order-theoretic terms can be found in the order theory glossary.

Read more about Order Theory: Background and Motivation, Basic Definitions, Functions Between Orders, Special Types of Orders, Subsets of Ordered Sets, Related Mathematical Areas, History

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**Order Theory**

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