What is GIS
GIS is a combination of
Hardware - Computers
Powerful software
Special data
A Thinking explorer
Far and away the most important element of the quartet above is the thinking explorer -- the user. The user manipulates the hardware, which engages the software, to work on the data.
The process is easy to describe:
Think about a place or a topic ...
Ask a question about it ...
Make a map ... Explore the number of Trees in your school yard
Explore the patterns that appear ... how many of the trees are Oak, how any Pine
Enhance the data or modify the analysis ...add details like height, color, thickness of trunk
Ask a new question ... like, how many 25 ft. Oak trees in our school yard
Repeat ...
GIS is not "canned maps." It is, instead, the ability to construct maps "on the fly," showing what you want (and have data for) in the way you define. The software draws the integration of data: geographic features (or "where things are") and sets of attributes (or "what things are like"), processed according to rules you set. This requires high computer power, since you can draw an infinitely variable set of data at infinitely variable scales.
Why use GIS? To explore relationships between features that are distributed unevenly over space. The user can seek patterns that may not be apparent without using advanced techniques of query, selection, analysis, and display.
Here's a simple analogy: Imagine a set of map transparencies about an area,
one transparency for each feature type (land use, elevation, ethnicity, dominant language,
electrical wiring, transportation corridors, soil types, etc.). You can overlay the desired
transparencies, zoom to the desired scale, and ask questions that display relationships across
layers. You can also change the questions, scale, or layers, make a new display, and seek new
understanding.
"New Age Spreadsheet"?? As the computer spreadsheet changed the way people organized and used information in the 1980s, so is GIS doing the same thing today, though in a much more powerful way. GIS facilitates wise use of limited resources by clarifying characteristics and patterns over space. It's especially useful for problem-solving situations.
GIS also encourages people to collaborate. Rather than everyone working to create their own sets of data on the same subject, the data can be created once by specialists and shared by many. This means people can spend less time on low-end tasks that duplicate effort and more time focusing on higher level analyses.
Examples of situations where GIS can help:
Does it make sense to put a megamall here?
Should legislative district boundaries go here or there?
Do we expand the existing airport here or build a new one there?
Will there be enough schools for students here in 10 years?
Which pockets of endangered environment should we protect?
What is the impact of released waste on local health patterns?
Where might restocking of native species be environmentally wise?
Are we adequately prepared to service the local and surrounding population in the event of various possible disasters? For each situation, what are the important pieces of information that should be known in order to get "the right answer"? These pieces become the "layers" of information in the data set.
People have used GIS for a number of years, but only recently has the power of GIS been able to make its way into desktop computers. Originally used by professionals in research, government, and industry, it was restricted to those with dramatic computing power and lots of time to learn a complex tool. Today, basic GIS is easy to learn (even for adults) and fun to use (even for kids), and its technology is widely available. GIS is a way for learners of all ages to investigate important locations and topics, grasp key geographic patterns and principles, and engage in higher-level thinking and problem solving.