What is GIS?
The first step is to write a project plan. Project Work Plans (PWP) are used to ascertain your
hardware, datq training and staff support needs and to ensure that the appropriate resources are
available. The purpose of a PWP is to outline the scope of work related to a project. It is the
major planning and communication tool within the GIS section as well as between the GIS
Section, Division Heads and the user community at large.
The PWP is drailed before a new project is begun. It should then be discussed with the Division
heads, who will route it to the appropriate GIS staH. As work on the project proceeds, the PWP
may be modified to reflect changes in scope, timetable, or deliverables. Each modification
should be dated, discussed and re-routed.
Each PWP should include the following areas:
Overview: This is a brief overview of the intended project.
Proiect Descri~tion: A brief description of the project.
Purpose: Why the project is needed, and why GIS has been determined to be the appropriate
tool.
Proiect Goals and Objective Time Line: An outline of goals and objectives listed with a
realistic time line.
Promess to Date: Objectives which have been successfully completed. This is to be updated
as the project progresses.
Proiect Sume: Gqgraphic region covered by the project, data sets to be used or analyzed,
other software to be integrated, etc.
Proiect Objectives: Usually a detailed list of questions to be answered, or action steps to be
accomplished.
Proiect Deliverables: The results (maps, databases, files, processes, applications) of the
project.
StafT Requirements and Responsibilities: Include GIS staff, division, and other staff necessary
to make project successful. Include list of responsibilities of each staff.
Once the areas of the project work plan have been defined and documented, then soliciting for
support is easy. Each project must have management support. If management is supportive,
then budgeting is less worrisome. Experience proves, when documentation and research back an
ide~ the idea is usually more solid and wins approval. This plan has helped in many cases to
assist new and non GIS staff get started and provide valuable guidelines, in addition to winning
management support. It is important and encouraged, that this plan be compiled by the entire
GIS team. This allows for a smoother implementation and creates team work early in the
project.
The next step - “How do I implement a GIS? When you have pwpedy and realistically
planned for a GIS project, implementation is much easier. All the data conversion, collection or
input issues have already been thought through and documented. Ideas, goals and deliverables
have been established and defined. Division heads and managers have been interviewed and
have voiced needs. When management support and a budget has been cent%-med,
implementation can begin.
There are many other areas to learn about GIS and we only chose a few basics to discuss in this
paper. Attached is a list of recommended readings for additional information and knowledge for
novice GIS users and stafl’. Remember, data is the key to a successful GIS.
GIS Terminology
accuracv - The degree of correctness of a measurement, or degree of conformity with a
standard. Accuracy relates to the quality of a result, and is distinguished from precision, which
relates to the quality of the operation by which the result is obtained.
accuracy standards - Specific standards to which a finished product must adhere.
arc- Location data representing linear features or the borders of polygon features.
area - A two-dimensional defined space expressed as a spatial measurement.
attribute - Descriptive characteristic of a feature.
asimuth - Horizontal direction of a line measured clockwise from a reference plane, usually the
meridian.
base data - Basic level of map data. Other data is placed on top of base data for comparison or
geographic correlation. Most often referred to a base map.
base line - Starting point to which fiture changes will be compared.
benchmark - Series of tests for hardware and software needs assessment.
centroid - an average point in the polygon representing all points in the area.
comtmter aided deshm and drafthu (CADD] - Engineering and Architectural design and
draf%ng sofbvare.
commter aided reaming (CA Ml - Standard mapping operations software.
contour - An imaginary line depicting elevation on a map.
coordinate - Any of a set of numbers that gives the location of a given point.
Coordinate geometry (COGO] - A data entry method that accepts data in the form of survey
data (bearings and distances), and calculates coordinates for points.
database - A collection of data arranged for ease of retrieval.
database mana~ement system (DBMS) - soflware designed to manage a database.
data capture - Method used for converting raw or paper data into a computer system.
data dictionary - Describes and outlines the contents of a database.
ditital data - Tabular or locational information converted to digital form for use with
computers.
digitizing - The process of converting paper maps into a digital format for use with computers.
edge matching - The process of identifying a common point where a line or symbol crosses a
shared border of two adjacent maps.
feature - Basic geographic elements used to represent physical and cultural features on the earth
represented by points, lines and polygons.
geocoding - Assigning locational coordinates to map features based on an earth based coordinate
system.
grid - A pattern of lines forming squares used as a reference for locating points on a map.
layers- ovel-laYs of data that de~ with one theme. LaYers should have the s~e ~ordinate
system.
line - One-dimensional object having a length and direction which connects to at least two (2)
points.
map projection - Systematic drawing of lines of a plane surface to represent the parallels of
latitude and the meridians of longitude of the earth.
node - A common point between two (2) or more line segments.
point- Map symbol that refers to an object that has no dimension.
polygon- Atwo-dimensional fiiwwiththree (3 ormore=Cs whichintersect atPoin~ or
nodes forming an area.
raster - Computer assisted cartography created by a pattern of dots that give the appearance of a
somewhat abstract map.
rubbersheeting - Process of stretching and shrinking an area or portion of a map or image to fit
within selected control points.
scale - Ratio of the distance between two points on a map and the earth distance between the
same two points.
source material or data - Any type of data required for implementation of a GIS. (Examples
include: aerial photos, maps (paper and digital), charts, sketches, written reports, etc.)
smtial data - Data applying the location of geographical entities with their spatial dimensions
which are points, lines, area or surface.
topography - The configuration of the surface of the earth.
topology - Refers to the spatial relationships between the points and lines that define geographic
features.
vector - One dimensional data comprised of coordinate representations of locations on the earth
as points, lines, and polygons.
Acronyms and Abbreviations
AM/FM - Automated Mapping/Facilities Management
ASPRS - American Society for Photogrammetry and Remote Sensing
CADD - Computer aided drafting and design
CD-ROM - Compact-disk read only memory
COGO - Coordinate geometry
DBMS - Database management system
DEM - Digital elevation model
DLG - Digital line graph
DTM - Digital terrain model
EDM - Electronic data management
FGCC - Federal Geodetic Control Committee
GIS - Geographic Information System
GPS - Global Positioning Systems
IGES - Initial graphics exchanges standards
LRIS - Land related information system
NAD 83- North American Datum of 1983
NIWAS - National Map Accuracy Standards
PPs - Precise positioning services
SIF - Standard information format
SPOT - Satellite Probatoire pour l’Observation de la Terre
TIFF - Tag image file format
TIGER - Topologhxdly integrated geographic encoding and referencing system
TIN - Triangulated irregular network
URISA - Urban and Regional Information Systems Association
USGS - United States Geological Survey
UTM - Universal Transverse Mercator
WGS 84- World Geodetic System 1984
Suggested Readings for Introduction to GIS
GIS BOOK -by Geroge B. Korte, P.E.
Geographic Information System by Tor Bernhardsen
Geographic Information Systems Information Svstems An Introduction by Jeffery Star and John Estes
GIS Data Conversion Handbook by Glenn E. Mongomery and Harold C. Schuch
