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In-Depth Information
and so on. The growth of this market is an indicator of the importance that geography
plays as a common factor between different datasets. When it has been established
that data collected by one organization about a particular place refers to the same
place as the data collected by another organization, the data can be combined.
3.5.1.2 Standards Develop
At around this time, there was another significant advance: industry standards started
to be developed. Even by the mid-1990s most GIS could at most interoperate on the
level of importing or exporting the data formats of other vendors. Standards for GI
began to develop in part as a response to the lack of interoperability between GIS
and in part as a need to ensure existing standards such as SQL did not fragment. The
Open Geospatial Consortium (OGC) has been the main driving force behind stan-
dards development. Formed in 1994, OGC has grown to be an industry body with a
membership of several hundred organizations and universities with an interest in GI.
The Simple Feature
4
Model, Geography Markup Language (GML) (International
Organization for Standardization [ISO] 19136:2007), Web Map Server (WMS) stan-
dard (ISO 19128:2005), and the Web Feature Server (WFS) standard (ISO 19142:2010)
are probably the four most significant standards to have arisen from OGC. All of these
standards were emergent in the early 2000s and were influenced by the GIS Layer
model, the OO paradigm, and the need to transport GI across the Web. However, they
were largely written by and for the GI community—those interested in GIS analysis
or producing digital mapping of some form or other in a professional context. Hence,
they are an inwardly looking set of standards to be used within a community and
are not well known beyond it. Due to their origin and focus, the standards are also
geometry-centric by design. As a result, their uptake has been largely restricted to
the GI community. In comparison, the Keyhole Markup Language (KML), which
serves a similar purpose to GML, was created outside the GI community
5
and is very
popular with those wishing to exchange mapping data. KML has also become an
OGC standard, but only after KML had already become very well established among
nonprofessional users as well as many professionals outside the GI community.
3.5.1.3 The Web
In 1989, Tim Berners-Lee, a computer scientist working at CERN (European
Organization for Nuclear Research), proposed what would become the World Wide
Web (Berners-Lee, 1989), and in 1990 along with Robert Cailliau proposed Hypertext
to link documents on the Web (Berners-Lee and Cailliau, 1990). From that point, the
dramatic rise of the Web has been well documented. It was not long before mapping
began to emerge on the fledgling Web. Possibly the best-known early example was
the Map Viewer application built by Steve Putz at Xerox PARC (Palo Alto Research
Center) in 1993 (
Figure 3.8
) (Longley et al., 2001). Looking very crude by modern
standards, it nonetheless had all the features that we consider to be essential to any
modern map viewer, including pan and zoom functionality.
People also began to incorporate simple maps into Web-based applications; for
example, trade directories could show a map of where a particular service provider
was located, local authorities showed development plans, and environmental bodies
were able to report on flood risk areas and pollution. GIS companies were also quick
