# Code-Point with Polygons Getting Started Guide

Code-Point with Polygons is a dataset that contains the notional area of postcode units, allowing customers to display and analyse any data collected at the postcode level.

The polygons within the product are derived from georeferenced Royal Mail Postal Address File (PAF) delivery addresses. A process is undertaken to create a set of polygons around individual address records within a postcode. This is called a Thiessen process and the polygons are the result of a mathematical computation that creates polygons from point data. In this way, mathematically consistent boundaries are created between distinct postcode groups, creating this notional boundary set.

<figure><img src="/files/iu9PHJKXg3PE6e6stVko" alt="An image of a map showing Polygons containing postcodes as supplied in the Code-Point with Polygons product using a green outline"><figcaption><p>Polygons containing postcodes as supplied in the Code-Point with Polygons product</p></figcaption></figure>

Postcode unit boundaries are, by definition, only the delivery point or collection of delivery points that constitutes the postcode units. The boundary is therefore a notional one, the position of which is arbitrary. What has been created, however, is a set of boundaries that follows a consistent logic and portrays the notional footprint of each postcode unit. The boundary encloses every delivery address for which positional data of sufficient quality is available, and which follows major physical features that could reasonably be regarded as part of the postcode boundary.

This getting started guide focusses on using the product in shapefile, MapInfo TAB file and MapInfo MID / MIF formats. For guidance on using the product in vector tiles or GeoPackage formats please see the following getting started guides:

* [Getting Started with Vector Tiles ](/os-downloads/resources/product-resources/getting-started-with-geopackage-and-vector-tiles-guides/getting-started-with-vector-tiles.md)
* [Getting Started with GeoPackage](/os-downloads/resources/product-resources/getting-started-with-geopackage-and-vector-tiles-guides/getting-started-with-geopackage.md)

## Index

This getting started guide includes the following sections:

* [Using the vertical street lookup](/os-downloads/products/areas-and-zones-portfolio/code-point-with-polygons/code-point-with-polygons-getting-started-guide/using-the-vertical-street-lookup.md)
* [Creating single-space postcode](https://docs.os.uk/os-downloads/products/areas-and-zones-portfolio/code-point-with-polygons/pages/7mzSHdZoMyI8SDv6qAQR#id-3.1-centroids-and-polygons)
* [Data measures](/os-downloads/products/areas-and-zones-portfolio/code-point-with-polygons/code-point-with-polygons-getting-started-guide/data-measures.md)


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