Internet GIS, or Internet geographic information system (GIS), is a term that refers to a broad set of technologies and applications that employ the Internet to access, analyze, visualize, and distribute spatial data.[1][2][3][4][5] Internet GIS is an outgrowth of traditional GIS, and represents a shift from conducting GIS on an individual computer to working with remotely distributed data and functions.[1] Two major issues in GIS are accessing and distributing spatial data and GIS outputs.[6] Internet GIS helps to solve that problem by allowing users to access vast databases impossible to store on a single desktop computer, and by allowing rapid dissemination of both maps and raw data to others.[7][6] These methods include both file sharing and email. This has enabled the general public to participate in map creation and make use of GIS technology.[8][9]
Internet GIS is a subset of Distributed GIS, but specifically uses the internet rather than generic computer networks. Internet GIS applications are often, but not exclusively, conducted through the World Wide Web (also known as the Web), giving rise to the sub-branch of Web GIS, often used interchangeably with Internet GIS.[10][11][12][4][5] While Web GIS has become nearly synonymous with Internet GIS to many in the industry, the two are as distinct as the internet is from the World Wide Web.[13][14][15] Likewise, Internet GIS is as distinct from distributed GIS as the Internet is from distributed computer networks in general.[1][4][5]
Internet GIS includes services beyond those enabled by the Web. Use of any other internet-enabled services to facilitate GIS functions, even if used in conjuncture with the Web, represents the use of Internet GIS.[4][5] One of the most common applications of a distributed GIS system, accessing remotely saved data, can be done through the internet without the need for the Web.[4][5] This is often done in practice when data are sensitive, such as hospital patient data and research facilities proprietary data, where sending data through the Web may be a security risk. This can be done using a Virtual private network (VPN) to access a local network remotely.[16] The use of VPN for these purposes surged during the COVID-19 pandemic, when employers needed to allow employees using GIS access to sensitive spatial data from home.[17][18][19]