Components of GIS

Components of GIS:

            Integration of 3 components: Hardware and Software, data and people

1. Hardware and Software:

ü  Devices used by the end users such as plotters or graphic devices, scanners.

ü  Data Storage and manipulation is done by a range of processors

ü  Web servers for web applications

ü  Software which is based on their applications

ü  GIS follows 3 tier architecture

2. Data:

            Geographic data can be divided into vector and raster

            Vector:

ü  Discrete objects represented by Lines, points and polygons.

ü  Lines are formed by connecting two or more points.

ü  Polygons are closed set of lines

            Raster:

§  Continuous grid of cells in two dimensions, It has two types:

·         Categorical- Every cell value is linked to a category in a separate table.

o   Ex: soil types, vegetation types, land suitability and so on.

·         Continuous- describes continuous phenomena in space.

o   Ex: Digital Elevation Models (DEM) –does not have an attribute/category table

3. People:

Involved in all phases of developing GIS system and in collecting data, has2 types of people:

ü  Cartographers & Surveyors- creates maps and survey the land.

ü  System users-collecting data, upload data to system, manipulate the system and analyze the result.