> For the complete documentation index, see [llms.txt](https://docs.os.uk/os-downloads/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.os.uk/os-downloads/products/addresses-and-names-portfolio/addressbase-premium/addressbase-premium-technical-specification/code-lists-and-enumerations.md).
# Code lists and enumerations
A code list or enumeration is a controlled set of values which can be used to populate a specific column. The diagram below shows the code list and enumeration UML models associated with AddressBase Premium with their appropriate descriptions:
The code list and enumeration UML models associated with AddressBase Premium.
## AddressBase Premium code lists and enumerations
* [CountryCode](/os-downloads/products/addresses-and-names-portfolio/addressbase-fundamentals/code-lists-and-enumerations/countrycode.md)
* [AddressBasePostalCode](/os-downloads/products/addresses-and-names-portfolio/addressbase-fundamentals/code-lists-and-enumerations/addressbasepostalcode.md)
* [BLPUStateCode](/os-downloads/products/addresses-and-names-portfolio/addressbase-fundamentals/code-lists-and-enumerations/blpustatecode.md)
* [ChangeTypeCode](/os-downloads/products/addresses-and-names-portfolio/addressbase-fundamentals/code-lists-and-enumerations/changetypecode.md)
* [LanguageCode](/os-downloads/products/addresses-and-names-portfolio/addressbase-fundamentals/code-lists-and-enumerations/languagecode.md)
* [LogicalStatusCode](/os-downloads/products/addresses-and-names-portfolio/addressbase-fundamentals/code-lists-and-enumerations/logicalstatuscode.md)
* [OfficalFlagCode](/os-downloads/products/addresses-and-names-portfolio/addressbase-fundamentals/code-lists-and-enumerations/officialflagcode.md)
* [StreetRecordTypeCode](/os-downloads/products/addresses-and-names-portfolio/addressbase-fundamentals/code-lists-and-enumerations/streetrecordtypecode.md)
* [RPCCode](/os-downloads/products/addresses-and-names-portfolio/addressbase-fundamentals/code-lists-and-enumerations/rpccode.md)
* [USRNMatchIndicatorCode](/os-downloads/products/addresses-and-names-portfolio/addressbase-fundamentals/code-lists-and-enumerations/usrnmatchindicatorcode.md)
* [StreetStateCode](/os-downloads/products/addresses-and-names-portfolio/addressbase-fundamentals/code-lists-and-enumerations/streetstatecode.md)
* [StreetClassificationCode](/os-downloads/products/addresses-and-names-portfolio/addressbase-fundamentals/code-lists-and-enumerations/streetclassificationcode.md)
* [StreetSurfaceCode](/os-downloads/products/addresses-and-names-portfolio/addressbase-fundamentals/code-lists-and-enumerations/streetsurfacecode.md)
* [FileTypeCode](/os-downloads/products/addresses-and-names-portfolio/addressbase-fundamentals/code-lists-and-enumerations/filetypecode.md)
* [PostcodeTypeCode](/os-downloads/products/addresses-and-names-portfolio/addressbase-fundamentals/code-lists-and-enumerations/postcodetypecode.md)
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