GI and Cartography Issues - A Primer of GIS: Fundamental Geographic and Cartographic Concepts - page 64

peripherals can be part of the core computer hardware (CPU and memory)
necessary for the basic GIS software operations, but can include printers,
tape drives and external hard disks, monitors, digitizers, scanners, and so on,
that offer additional possibilities for working with the GIS.
Because of the complexity of the computing operations, GIS often
requires supporting organizations. Even a single person working with GIS
will want, or even need, help with the hardware, software, and peripherals
from time to time. The size of the GIS organization often goes hand-in-hand
with the size of the company or office where the GIS is being used. There
certainly is such a thing as “desktop GIS,” but no matter how good the mar-
keting, the complexity of GIS necessitates good support.
Beyond people, who are often not depicted in representations of GIS
organization, GIS also rely on measurements and conventions to a high
degree. These aspects, often abstract and implicit, are key parts of the under-
lying framework for all work with geographic information and maps. Of
course, without data, all the hardware, software, and peripherals will never
make a GIS.
Summary
The choices made for geographic representation and cartographic represen-
tation determine accuracy and quality. Fundamental choices involve projec-
tion, scale, and symbolization. A projection is used for all accurate geo-
graphic information and maps because the coordinates of almost all
geographic information is recorded in a two-dimensional coordinate system;
however, the earth is a three-dimensional object. It is possible to calculate
locations for geographic information or maps without using a projection,
but positional accuracy is lost. Other choices involving scale and symboliza-
tion are fundamental and are often included in the data modeling that goes
along with the geographic representation and cartographic representation.
Scale is important, for it determines the area and detail of geographic infor-
mation and maps. Symbolization leads to the meaning of symbols that
should assure accuracy and quality. Color is one of the most important sym-
bolization choices. Its use often follows established conventions. Beyond con-
ventions, the organization of GIS including software, hardware, and periph-
erals can have a very strong inf luence on the choices that can be made.
Review Questions
1. What GIS component is frequently overlooked in descriptions of
GIS?
2. What is the difference between a spheroid and an ellipsoid ?
3. How is a geoid used in relationship to an ellipsoid?
4. How is scale helpful for working with GI?
5. Why would some people claim all maps lie?