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Lakota Studies 400/600:  Special Topics:  Introduction to Geographic Information Systems and Science

Week 9 Notes:  The Internet and GIS

The Internet and GIS

In the early days of GIS, data users transferred data among themselves using physical media--nine-track reel tapes and other physical storage devices.   The size of the data sets made the transfer of the data cumbersome, and this increased GIS development costs and impeded the development of GIS in many ways.  The machines used were, in large part, Unix and Vax machines running on mainframe and minicomputers.   These storage devices were not compatible with PC GIS users who could not use them.  PC users' storage devices were largely limited to the floppy disk, which could not store more than a small vector data set, certainly not any satellite images or large vector file. 

The Internet has transformed the way in which spatial data is transferred.  The size of the files has increased, but the speed of Internet backbones has also increased, allowing for faster transfer of data, but more importantly, an increase in the use of spatial data as a result by more and more sectors of society.  Organizations such as a county government routinely set up Intranets, not accessible by anyone outside the organization, but are internal Internet servers that are incredibly useful for sharing data within the organization.  It has also reduced the error and problems caused by the update of multiple versions of the same spatial data file--say, by the assessors department and the public works department of a county.  GIS Intranets allow for a map library--where data is checked out, updated, and checked back in to one master database.  

The Internet has also transformed the way that spatial data is served from producers to users, beginning in the 1980s with file transfer protocol (FTP) sites.  These sites allowed users to break away from handling physical media.  Next, HTML pages in the 1990s on the World Wide Web allowed users more flexibility and ease of use.  Then, continuing in the late 1990s to today, FTP sites, web pages, and Internet Map Services (IMS) sites brought additional capability into the hands of GIS users.  IMS allows the data producer to host spatial data holdings of an organization online so that others can  download them, browse them, and even ask questions (queries) of the data with an ordinary web browser.  They often can also download from these sites.  The software allows users to integrate their own data on their own computers with data on the Internet, for display, query, and analysis.   Today, a data user can use data on IMS sites without downloading--while the data is still online.  For example,  with ArcGIS, a theme may be added while on the Internet, such as real-time weather data.  

Many excellent examples of IMS sites exist.  View the following sites:

The Sample IMS gallery at ESRI:  http://maps.esri.com 

The near-real time wildfire site:  http://www.geomac.gov 

The National Atlas Project:  http://nationalatlas.gov 

Look for these Internet trends to continue revolutionizing the world of GIS.

Back to SGU GIS Course Home

Author:  Joseph J. Kerski, Geographer, USGS, jjkerski@usgs.gov, 303-202-4315