What is it?
Geographic information systems are essentially digitised maps linked to data. From academic beginnings they spread to government and utility companies. More recently, they have entered commercial use, and there is huge potential for dynamically combining GIS with the location information provided by satellite positioning systems or mobile phone networks.
GIS skills can be used in a wide range of situations, from developing the tools and application programming interfaces that enable the systems to interact, to populating the systems and creating applications for them.
Where did it originate?
In 1959, Waldo Tobler devised a model called Mimo (map in, map out) for applying computers to cartography. The first non-academic application was developed in 1963 to analyse Canada's national land inventory. New York's Transportation Information System followed in 1968.
In the late 1960s, leading GIS suppliers ESRI and Intergraph were founded. The first web-based interactive map was developed in 1993, at Xerox Parc in California. More on the historical background of GIS can be found on the UK's Centre for Advanced Spatial Analysis website.
What is it for?
Applications listed on the Association for Geographic Information (AGI) website include land use analysis, transport management, health service planning, managing flood defences, monitoring pollution, emergency service command and control systems, tracking parcel delivery, buying and selling property, and locating retail stores.
What makes it special?
The power to combine almost any data source with location information has enormous potential. However, due to slow progress on standards development, it has so far been under-used.
How difficult is it to master?
With the move from proprietary workstations to PC and browser-based applications, systems have become much easier to use, and building a GIS can be a simple matter of dragging and dropping. But geographical information is also a demanding academic discipline, and the co-existence of multiple standards complicates application development and integration.
Geographic information processing relies on a number of unfamiliar, complex data types, and the AGI said that, without standards, users often end up with underutilised data, systems that are uneconomic to operate, weak integration with other business processes and a limited ability to respond to new technology. Users can find themselves constrained by the limitations of their suppliers.
Where is it used?
In academia, government, utilities, transportation, manufacturing, communications, retailing and healthcare. The TV series Time Team and Extreme Archaeology both make extensive use of GIS.
What systems does it run on?
Everything from supercomputers to handhelds. It is increasingly browser-based.
Not many people know that
The CIA spotted the potential of GIS and began using it in the 1960s.
What is coming up?
Standards and APIs to enable sharing of data and integration between different GIS and with other applications.
Those wanting to train in GIS have a choice between learning a package (from ESRI, Autodesk, MapInfo and Intergraph, among many others), or a university-based course (several distance learning courses are on offer). See the AGI site for a complete list of academic courses in the UK.
Rates of pay
Jobs include GIS analysts, digitisers, technicians, designers and developers. Digitisers tend to be the lowest paid. Rates vary from about £25,000 for GIS data analysts in local government to £30,000-£40,000 in commercial applications. There are plenty of contract opportunities.