# GeoPackage overview

GeoPackage (.gpkg) is defined by the Open Geospatial Consortium (OGC) as an open, non-proprietary, platform-independent, standards-based data format for geographic information systems (GIS). It is designed to be a lightweight format that can contain large amounts of varied and complex data in a single, easy-to- distribute and ready-to-use file. GeoPackage is natively supported by numerous software applications.

GeoPackage offer users the following benefits:

* The single file is easy to transfer and offers the end-user a rich experience.
* Attribute names are not limited in length, making the format user friendly.
* The file size limit is large at 140TB.

{% hint style="info" %}
A file size limit could be imposed by the file system to which the file is written.
{% endhint %}

* It supports raster, vector and database formats, making it a highly versatile solution.
* It is an OGC standard.
* In most cases, it is a plug-in-and-play format.

For general guidance on using the product in GeoPackage format, please see the [Getting started with GeoPackage guide](https://docs.os.uk/os-downloads/resources/product-resources/getting-started-with-geopackage-and-vector-tiles-guides/getting-started-with-geopackage).

For further information on GeoPackage, please see the [GeoPackage website](https://www.geopackage.org/).

## Attribute mapping <a href="#id-5.1-attribute-mapping" id="id-5.1-attribute-mapping"></a>

The naming of attributes between GeoPackage and GML is very similar as neither format limits the number of characters for an attribute name. The tables in the following pages map the GML attribute name to the GeoPackage attribute name:

* [RoadLink](https://docs.os.uk/os-downloads/products/transport-network-portfolio/os-open-roads/os-open-roads-technical-specification/geopackage-overview/roadlink)
* [RoadNode](https://docs.os.uk/os-downloads/products/transport-network-portfolio/os-open-roads/os-open-roads-technical-specification/geopackage-overview/roadnode)
* [MotorwayJunction](https://docs.os.uk/os-downloads/products/transport-network-portfolio/os-open-roads/os-open-roads-technical-specification/geopackage-overview/motorwayjunction)

{% hint style="info" %}
The GML contains an attribute which describes the geometry of the feature; this is not applicable to GeoPackage files as they are separated by their geometry.
{% endhint %}


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