# GeoPackage overview

OS MasterMap Topography Layer is supplied as six GeoPackage files (one file per feature type) for a user- defined area of interest (AOI) only. GeoPackage (\*.gpkg) is an open, standard, non-proprietary, platform- independent data format for geographic information systems (GIS), as defined by the Open Geospatial Consortium (OGC). 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 offers users the following benefits:

* The files are easy to transfer and offer the end-user a rich experience.
* Attribute names are not limited in length, making the format user-friendly.
* The file size limit is very large at 140 TB, so lots of data can be easily accommodated (please note that a file size limit may be imposed by the file system to which the file is written).
* 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-and-play format.

For information on how to open, use and understand a GeoPackage dataset, please refer to our [Getting Started with GeoPackage guide](/os-downloads/resources/product-resources/getting-started-with-geopackage-and-vector-tiles-guides/getting-started-with-geopackage.md). Further detailed information on GeoPackage can be found on the [GeoPackage website](https://www.geopackage.org/).

{% hint style="info" %}
It is not recommended that users download large AOIs of OS MasterMap Topography Layer in GeoPackage format as this will be too large a file for the majority of GIS to handle.
{% endhint %}


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