Basic Elements Of GIS

BASIC ELEMENTS/COMPONENTS OF GIS : 

Based on the functionality of a GIS, there are in general five components of a GIS namely , hardware, software, data, people, and methods. Some authors/books mention just first four of them, assuming methods as a part of software part. Present section discusses each of the five components. While figure 1 depicts components of a GIS, table 1 gives complete details of different elements.

• People
• Data
• Software
• Hardware
• Procedures/Methods

 

• People
• People are the most important part of a GIS
• People define and develop the procedures used by a GIS
• People can overcome shortcoming of the other 4 elements (data, software, hardware, procedure), but not vice-versa

• Data

• Data is the information used within a GIS
• Since a GIS often incorporates data from multiple sources, its accuracy defines the quality of the GIS.
• GIS quality determines the types of questions and problems that may be asked of the GIS

• GIS software

• It encompasses not only to the GIS package, but all the software used for databases, drawings, statistics, and imaging.
• The functionality of the software used to manage the GIS determines the type of problems that the GIS may be used to solve.
• The software used must match the needs and skills of the end user. 

• Popular GIS Software
• Vector-based GIS
• ArcGIS (ESRI)
• ArcView
• MapInfo
• Raster-based GIS
• Erdas Imagine (Leica)
• ENVI (RSI)
• ILWIS (ITC)
• IDRISI (Clark Univ.)

• Hardware
• The type of hardware determines, to an extent, the speed at which a GIS will operate.
• Additionally, it may influence the type of software used.
• To a small degree, it may influence the types/ personalities of the people working with the GIS.

• Procedures/ Methods
• The procedures used to input, analyze, and query data determine the quality and validity of the final product. 
• The procedures used are simple the steps taken in a well defined and consistent method to produce correct and reproducible results from the GIS system.

Table 1. Elements of GIS

 

Spatial/Graphical elements of GIS