In computing, GeoServer - an open source server written in Java (Java programming language) - allows users to share and edit geospatial data. Designed for interoperability, it publishes data from leading spatial data sources using open standards. GeoServer has evolved into a simple method of connecting existing information to virtual globes such as Google Earth and NASA World Wind (see also web-based maps such as OpenLayers, Google Maps, and Bing Maps). GeoServer serves as a reference implementation of the Open Geospatial Consortium Web Feature Service standard, and also implements the Web Map Service and Web Coverage Service specifications.

It was designed so that citizens could get involved in government and urban planning in 2001 through the Open Planning Project (The Open Planning Project, TOPP).[1]​ GeoServer is a non-profit organization.

GeoServer in turn gave rise to creating another Geographic Information System project called GeoTools, also based on Java as a tool kit. Another project related and contemporary with GeoServer is the one carried out by the Open Geospatial Consortium that regulates the Geographic Markup Language protocol (Geography Markup Language), an XML sublanguage for the modeling, transport and storage of geographic information.[2]​.

GeoServer aims to operate as a node through a free and open Spatial Data Infrastructure to offer geospatial data, just as Apache HTTP Server has done by offering a free and open web server to publish HTML.

Among the main features of Geoserver we can mention some such as:

Additionally, GeoServer includes an integrated OpenLayers client for previewing data layers.

GeoServer also supports publishing geospatial data to Google Earth through the use of network links, using KML for this. Advanced features available for Google Earth output include custom pop-up templates, altitude and longitude displays, and super-overlays.

GeoServer is based on GeoTools, a geographic information systems library.