# SNOMED CT Expressions

This chapter provides an introduction to SNOMED CT expressions and covers several aspects related to their representation and use.

It begins by outlining the key differences between pre- and postcoordination, including their relative benefits and limitations. It covers the syntax used to represent expressions, providing a detailed overview of the various expression parts and operators that are used. The chapter introduces the different forms that expressions can take, and it discusses the role of the concept model and editorial guidance required to ensure the accuracy and consistency of expressions.

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