Vocabulary
Geocaching
Geocode
GPS
GIS


GIS (Geographic Information System)


GIS is a computer system that captures, stores, queries, stores, and displays geographic data. In a more generic sense, GIS applications are tools that allow users to create interactive queries (user created searches), analyze spatial information, edit data, maps, and present the results of all these operations.
  • The main point of GIS is geocoding, which is the interpolating of spatial locations (X,Y coordinates) from street addresses or any other spatially referenced data such as ZIP Codes, parcel lots and address locations. Put locations into a digital format for mapping in a program.
  • Once the stored objects are combined, a map can be created with layers that depict different parts of human or environmental information.
  • GIS technology can be used for scientific investigations, resource management, asset management, archaeology, urban planning, cartography, criminology, marketing, logistics,...
  • GIS technology takes geocoded information and can then help to make decisions about the cause and effect of chemicals on the environment or people, the potential location of future crimes, the best location for a store, ...



There are a number of advantages to using this type of map as opposed to traditional ones:

-To start locations won’t be messed up on account of human error, as often occurs with cartographers drawing by hand.

-With GIS, maps objects can be added or removed, brightened or toned down in color, and mistakes corrected without having to redraw the map.

-The separate layers of the map also help those looking for specific information, such as if one was looking at boundaries of countries, bodies of water, roads, and names of place. GIS permits construction of much more complex maps than can be drawn by hand.

-The GIS map layers can be compared to each other to show relationships among different kinds of information. Eg. When trying to understand the impact of farming practices on water pollution, a physical geographer can compare a layer of vegetation with a layer of bodies of water.



GPS (Global Positioning System)

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GPS accurately determines the precise position of something on Earth. The system was developed by the U.S. Department of Defense and managed by the United States Air Force 50th Space Wing for military use but later become more widely commercial.
  • The system, such as the one used in the United States, has between 24 to 32 satellites placed in specific orbits, a series of tracking stations to monitor and control the satellites, and receivers that compute position, velocity, and time from the satellite signals. Its official name is NAVSTAR GPS and even though NAVSTAR is not an acronym, a few backronyms have been created for it.
  • The system is particularly useful in coding the precise location of objects and entering, which can be put in as a layer in a GIS later on.


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Uses
The most common use for GPS is in the navigation of aircraft and ships but is also now provided in cars. The system detects the vehicles position while the motorist provides the desired destination and instructions are given as to how to reach that destination.
The system can also be used when the motorist has an emergency since the exact location is known. Since it became fully operational, GPS has become a widely used aid to navigation worldwide, and a useful tool for map-making, land surveying, commerce, scientific uses, and hobbies such as geocaching.



Links:

http://en.wikipedia.org/wiki/Geographic_information_system(external link)

http://en.wikipedia.org/wiki/Remote_sensing(external link)

http://en.wikipedia.org/wiki/Global_Positioning_System(external link)

www.aero.org/education/primers/gps/GPS-Primer.pdf