What is GIS? / Geographic Information System (GIS)

INTRODUCTION TO 

GEOGRAPHIC INFORMATION SYSTEMS

YOU MIGHT ALSO LIKE: General Principles Of Gis/Gis: Definitions And Main Functions

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GIS: 

geographic information management for multiple business applications

GIS is: geographic data = digital maps

news geographically localized / geographic coordinates + geographic reference (map projection)

GIS is: computer equipment Specialized computer and peripherals

     

GIS is: issues related to territory

town / state / region / area ecological / natural area / agricultural area

land management : technical, economic ,legal/planning ,landed ,networks
different managers: general Council ,regional Council ,town /diren ,DDAF ,DDAF,dde

gis = decision support

GIS is: actors

• private stakeholders / public players 
• local  /national actors 

services of State  /communities territorial /business /providers of data /General public /users data administrator

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GIS:

• software
• cast
• equipment
• geographic data
• territory

-Def: a geographic information system and a set of digital data geographically localized structured within a data processing system

comprising functional modules allow:

• create and edit
• question
• question represent cartographically
• a database
• geographic
• according to criteria semantic and spatial.

terminology /GIS related fields:

• Remote sensing
• cartography
• database
• geographic Remote sensing
  
• Photo interpretation
• field survey DGPS
• statistical geostatistics
• online maps
• Mobile GIS
• treatment images
• System Spatially Referenced Information
• The system of the Territory Information

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chapter 2

Examples of using the GIS:

-With the gis, we will : 

map /manage /analyze spatially
-the different component of our geographical environment:
forest /urban area /agricultural crop /ground /network transport /network landscape distribution

-GIS what is it for?

• cartography Natural Resources
• fleet tracking trucks, trains, taxi
• Emergency Response fire service, ambulance. ..
• mapping and monitoring networks: roads, energy, water, telephone
• Location risk natural and technology
• management of rural areas: agricultural exploitations, parks, forests. . .
• Route calculation
• facilities: rural/ road /rained
• geomarketing
• studies impact

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DATABASES ORIGIN OF GIS

DBMS: Database Management Systems
Databases as the foundation of GIS: Introduction to DBMS

How is the information in a database?

• users 
• process transactions
• database

files and data storage

What difference?

-spreadsheet: The spreadsheet is fully charged
RAM: the limited size of data

-database: The database works "directly"
HDD: virtually unlimited data size

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structure of relational databases:

• database: table 1 -----table2-------table3

• table1 ------recording 1 -------recording 2

• recording 2 -----field 1-----field2-------field3
  

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table of relational databases:

The relational model introduced by Ted Codd in the 70:

• attribute = field = column

• line recording individual
  

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concept identifier or key:

• id = code uniquely identifies each record in the table

• How many uniquely identify information record in the table?

• duplicates (two or more identical information) are prohibited

• the presence of the key prohibits the presence of an empty field in a record.
  

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why separate the information into multiple tables:

2 types of information in the same table:

• owners fields

• vehicles fields

Separation of information into several tables allows

better modularity information that speeds up searches by queries on large amounts of information avoiding unnecessary handling of information