> For the complete documentation index, see [llms.txt](https://docs.snomed.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.snomed.org/snomed-ct-practical-guides/snomed-ct-terminology-services-guide/4-terminology-service-types.md).

# Terminology Service Types

This section describes services required to enable effective use of SNOMED CT. The guide does not mandate a particular way to meet these requirements. In some cases, a single terminology service API call may address several of the requirements identified in this section of the guide. In other cases, multiple API calls may be required to address a single requirement.

* [Select Edition and Version](/snomed-ct-practical-guides/snomed-ct-terminology-services-guide/4-terminology-service-types/4.1-select-edition-and-version.md)
* [Get a Concept, Description or Relationship](/snomed-ct-practical-guides/snomed-ct-terminology-services-guide/4-terminology-service-types/4.2-get-a-concept-description-or-relationship.md)
* [Get Terms for a Concept](/snomed-ct-practical-guides/snomed-ct-terminology-services-guide/4-terminology-service-types/4.3-get-terms-for-a-concept.md)
* [Get Definition of a Concept](/snomed-ct-practical-guides/snomed-ct-terminology-services-guide/4-terminology-service-types/4.4-get-definition-of-a-concept.md)
* [Get and Test Concept Subtypes and Supertypes](/snomed-ct-practical-guides/snomed-ct-terminology-services-guide/4-terminology-service-types/4.5-get-and-test-concept-subtypes-and-supertypes.md)
* [Get and Test Reference Set Membership](/snomed-ct-practical-guides/snomed-ct-terminology-services-guide/4-terminology-service-types/4.6-get-and-test-reference-set-membership.md)
* [Validate and Apply Expression Constraints](/snomed-ct-practical-guides/snomed-ct-terminology-services-guide/4-terminology-service-types/4.7-validate-and-apply-expression-constraints.md)
* [Find Concepts](/snomed-ct-practical-guides/snomed-ct-terminology-services-guide/4-terminology-service-types/4.8-find-concepts.md)
* [Identify Changes to the Terminology](/snomed-ct-practical-guides/snomed-ct-terminology-services-guide/4-terminology-service-types/4.9-identify-changes-to-the-terminology.md)
* [Get Data from a Reference Set](/snomed-ct-practical-guides/snomed-ct-terminology-services-guide/4-terminology-service-types/4.10-get-data-from-a-reference-set.md)
* [Get History Data](/snomed-ct-practical-guides/snomed-ct-terminology-services-guide/4-terminology-service-types/4.11-get-history-data.md)
* [Get Mapping Data](/snomed-ct-practical-guides/snomed-ct-terminology-services-guide/4-terminology-service-types/4.12-get-mapping-data.md)
* [Get Concept Model Rules](/snomed-ct-practical-guides/snomed-ct-terminology-services-guide/4-terminology-service-types/4.13-get-concept-model-rules.md)
* [Validate Concept Definitions and Expressions](/snomed-ct-practical-guides/snomed-ct-terminology-services-guide/4-terminology-service-types/validate-concept-definitions-and-expressions.md)
* [Test Expression Subsumption](/snomed-ct-practical-guides/snomed-ct-terminology-services-guide/4-terminology-service-types/4.15-test-expression-subsumption.md)

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