# OS Open Names Overview

OS Open Names is a geographic directory that contains basic information about identifiable places (i.e. named places). The content of the product is divided into themes based on type and local type classification values. The data contains accurate and current settlement names, road names and numbers, postcodes and their locations, with additional contextual information and links to other datasets. It is designed for use across all market sectors and can be used for web service and mobile development.

In addition to the data product, OS Open Names content is available through the OS Names API (application programming interface), which is accessible via the [OS Data Hub](https://osdatahub.os.uk/).

The primary use of the product is to provide the location for a named place to support a wealth of activities such as discovery, identification, visualisation, geocoding, routing and navigation, and linking diverse information.

The name of the place is the key property used for querying. It is also recognised that a place may have multiple names as its official name may be defined in multiple languages (English / Welsh or English / Gaelic), for example, Cardiff (English) and Caerdydd (Welsh). Where relevant, we give a second name, with the language being specified.

Names are not unique, so additional location information is provided to enable users to refine their query to select the named place they are interested in. Additional location information includes postcode district, populated place, district / borough, county / unitary authority, European region, and country.

The OS Open Names specification will extend the Infrastructure for Spatial Information in the European Community (INSPIRE) Geographical Names theme to ensure that it is compliant with European open data initiatives.

<figure><img src="https://1897589978-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FcNpJpLP8RROUaWVQo5ea%2Fuploads%2FEBUz18ZJot1FHlERJV4x%2F1.png?alt=media" alt="Screenshot of OS Open Names centred over Covent Garden in central London, UK. Local type classifications are shown by coloured circles of various sizes (e.g. Named Road, Numbered Road, and Postcode)."><figcaption><p>The range of features included in OS Open Names.</p></figcaption></figure>

OS Open Names has a resolution of 1 metre. The definition of how the locations are generated is outlined in the [Technical Specification](https://docs.os.uk/os-downloads/products/addresses-and-names-portfolio/os-open-names/os-open-names-technical-specification).

The persistent unique identifier enables features to be quickly and easily identified and can be used for better data management. The exceptions to this are Section of Named Road and Section of Numbered Road, which don’t have a persistent identifier. More information on this can be found in the [Technical Specification](https://docs.os.uk/os-downloads/products/addresses-and-names-portfolio/os-open-names/os-open-names-technical-specification).

The links to other gazetteers, such as DBpedia and GeoNames, encourage wider use of the product and enable users to embed it more easily into their systems and processes if they already use one of these gazetteers.

The contextual geography attributes, such as DISTRICT\_BOROUGH, enable features with the same name to be identified quickly through enhanced querying for greater accuracy of results.

Bounding boxes, or Minimum Bounding Rectangles (MBR), are given for roads and settlements. These can be used to quickly zoom to the extent of a feature in a GIS (geographic information system) map widow, application or web service.

## How to use the data <a href="#id-1.1-how-to-use-the-data" id="id-1.1-how-to-use-the-data"></a>

For guidance on using the data, please refer to the [Getting Started Guide](https://docs.os.uk/os-downloads/products/addresses-and-names-portfolio/os-open-names/os-open-names-getting-started-guide).


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