An introduction to

1
An introduction to
G I S
2

• AIM To introduce the basic principles of GIS
• After this lecture you should be able to
• Provide a definition, and brief description of
  the historical development, of GIS
• Describe the main components required to run a
  successful GIS
• Give examples of some GIS applications

3
What is GIS?

• A technology
• hardware software tools
• An information handling strategy
• The objective to improve overall decision making

4
GIS a formal definition

• A system for capturing, storing, checking,
  integrating, manipulating, analysing and
  displaying data which are spatially referenced to
  the Earth. This is normally considered to involve
  a spatially referenced computer database and
  appropriate applications software
• Chorley Report, 1987

5
Why is GIS unique?

• GIS handles SPATIAL information
• Information referenced by its location in space
• GIS makes connections between activities based on
  spatial proximity

6
GIS concepts are not new!

• London cholera epidemic 1854

7
Spatial information handling 1854
8
GIS historical background

• This technology has developed from
• Digital cartography and Computer-Aided Design
  (CAD)
• Data Base Management Systems (DBMSs)

9
GIS components
Spatial data
?
G I S
Computer hardware / software tools
Specific applications / decision making
objectives
10
Types of data
Spatial
NON-spatial
Maps
Schematic diagrams
Images
Oblique photographs
Videography
Films
ZIP codes
Financial statements
60004 60126 60056
12,000 23.45 56789 23,456 12.45
23456 45,987 29.57 87634
11
What makes data spatial?
Grid co-ordinate
Placename
Latitude / Longitude
ZIP code
Description
Distance bearing
12
Software hardware tools

• High End toolkits
• Desktop Mapping
• Web enabled
• Components

13
Manipulation and analysis

• What would happen if . . .
• A chemical leaked into a river?
• Where does . . .
• The Dan Ryan exist in relation to the City?
• Has . . .
• Population changed over the last ten years?
• Is there a spatial pattern related to . . .
• Car ownership in our area?

14
GIS is comprised of

• Data input
• Storage
• Management
• Analysis
• Output

15
The benefits of GIS include

• Better information management
• Higher quality analysis
• Ability to carry out what if? scenarios
• Improve project efficiency

16
GIS Applications

• Facilities management
• Marketing and retailing
• Environmental
• Transport/vehicle routing
• Health and Emergency 9-1-1
• Insurance
• and many more . . .