# GeoPackage overview

OS MasterMap Water Network Layer is supplied as a single GeoPackage for the whole of Great Britain. GeoPackage (\*.gpkg) is an open, non-proprietary, platform-independent, standards-based 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 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 very large at 140TB (A file size limit might 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 taken from the [GeoPackage website](https://www.geopackage.org/).

The following page covers [attribute naming differences](/os-downloads/resources/product-resources/end-of-life-product-documentation/os-mastermap-water-network-layer/os-mastermap-water-network-layer-technical-specification/geopackage-overview/watercourselink.md) between GML and GeoPackage formats for the two feature types in the product.


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