data that involves an aspect of location on the earth’s surface or near surface which is converted to a form that is meaningful to a user
geographic information/spatial information
a system of hardware, software, and procedures designed to support the capture, management, manipulation, analysis, modeling and display of spatially referenced data
geographic information system
set of computer based systems for managing geographic data and using these data to solve real world spatiall problems
geographic information system
paper map - static, snapshot of real world at a given time only
Conventional data
dynamic; allows a range of functions for storing, processing, analyzing and visualizing spatial data
digital geographic data
hardware, softwqare, data, methods, people
5 components of GIS
computer system on which the GIS software will run used for acquisition, storage, analysis and display of geog information
hardware
provides the functions and tools needed to store, analyze, and display geog information
software
core of GIS
data
images, census, surveys
primary data capture
maps, plans
secondary data capture
GIS users range from technical specialist who design and maintain the system to those who use it to help them perform their everyday work
people
various techniques used for map creation and further usage for any project. models to come up with the desired products.
methods
representation of the real world geogrpahic features in digital form to be stored in a GIS database.
geographic data models
the world is a continuous field in 2 or 3 dimensions. raster data model, e.g. elevation, soils
field-based model
well defined (discreet) boundaries such as buildings and roads, or diffused (fuzzy) boundaries such as forests and beaches. vector data model
object based model
area is covered by grid with equal-sized square cells containing an attribute value for each.
raster
features in the real world are represented either as points, lines, or areas, (polygons)
vector
adjacency, containment, connectivity
topological relationships
software designed to organize the efficient storage, manipulation, and access to data within an integrated database
database management system (DBMS)
contains geographic data of a particulat subject for a particular area
geographic database
a collection of tables or relaltions that can be connected to each other by keys.
relational DBMS
manipulation of spatial data into various forms to be able to extract additional and meaningul information to understand the real world. to identify the PATTERN.
spatial analysis
creates a composite map. an operation that superimposes multiple data
overlay