# Code list and enumerations

A code list or enumeration is a controlled set of values which can be used to populate a specific column. The code list and enumeration UML models associated with AddressBase are shown in the diagram below:

<figure><img src="/files/RFndtjSP3m1tDmJIBpW6" alt="UML diagram providing details of the code list and enumerations in the AddressBase product"><figcaption><p>UML diagram providing details of the code list and enumerations in the AddressBase product.</p></figcaption></figure>

## AddressBase code list and enumerations

* [CountryCode](/os-downloads/products/addresses-and-names-portfolio/addressbase-fundamentals/code-lists-and-enumerations/countrycode.md)
* [RPCCode](/os-downloads/products/addresses-and-names-portfolio/addressbase-fundamentals/code-lists-and-enumerations/rpccode.md)
* [ChangeTypeCode](/os-downloads/products/addresses-and-names-portfolio/addressbase-fundamentals/code-lists-and-enumerations/changetypecode.md)
* [PostcodeTypeCode](/os-downloads/products/addresses-and-names-portfolio/addressbase-fundamentals/code-lists-and-enumerations/postcodetypecode.md)


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