Geographic Information System (GIS) Definition
Geographic Information Systems, or GIS, are computer and software tools for gathering and analyzing data connected to geographic locations and their relation to human or natural activity on Earth. GIS data can be used to gather and analyze data about the surface of the earth, and to create layered maps, charts and 3D models of geographical features including mountains, rivers, forests, streets or buildings. Industries and governments use GIS tools to better understand everything from urban planning to climate change.
What is GIS?
GIS is an acronym for “Geographic Information System.” A GIS system uses computers and software to gather, manage and analyze data based on geography, and visualizes the data on a map. GIS mapping software uses spatial data to create maps and 3D models out of layers of visual information, revealing patterns and relationships in the GIS data. Many industries and governments use GIS to better communicate complex information and solve problems associated with geographic locations.
How GIS Works
GIS systems generally consist of the following elements:
- Maps — Shareable maps that contain geographic data layers.
- Data — Spreadsheets, tables and imagery with a geographic component that ties data to a particular location.
- Analysis — Spatial analysis enhances decision-making process by providing insights that give users more confidence when interpreting and predicting situations.
- Apps — GIS is no longer tied to a desktop. Mobile apps allow GIS data to be used anywhere, at any time.
While each application is different, Geographic Information Systems are broadly similar in the way they work. All GIS tools analyze and visualize spatial data, which includes location information like address, latitude or longitude.
Geographic Information Systems generally perform these tasks in three steps:
- Visualize data — Geographic data is displayed in GIS software.
- Combine data — Layers of data are combined to form maps.
- Query data — Geographic queries search for values in layered data.
What is the Purpose of Geographic Information Systems?
Geographic Information Systems, or GIS, overlay data on a map. By connecting data with geography, GIS programming helps people understand how data relates to a specific location. Visualizing data geographically can help people spot patterns that would have been difficult or impossible to detect in a huge spreadsheet.
GIS maps are used in a variety of ways, from tracking climate change to analyzing crime patterns. Many companies use Geographic Information Systems, and GIS technology is integrated into nearly every industry and government organization. Environmentalists were some of the earliest adopters, using GIS to track melting glaciers and deforestation. The agricultural industry relies on GIS to map crop and soil types.
Businesses use GIS to pick store sites, manage their supply chain and profile their customers. GIS applications help real estate companies and land planers compare locations and parcels. Journalists use GIS to illustrate concepts for their audience. GIS data can also effectively target ad campaigns.
The military relies heavily on GIS to manage logistics, location intelligence and satellite data.
Local police forces use GIS for predicting policing and investigative analysis. GIS has also revolutionized public health and safety by visualizing the spread of disease. For similar reasons, GIS has become a vital tool for disaster response.
Today, GIS continues to expand into diverse areas including archaeology, education and transportation.
Benefits of GIS (Geographic Information Systems)
GIS benefits businesses and governments by giving them the ability to ask complex questions about location-based data.
GIS uses spatial analysis to provide visual clues that help people discover deeper insights than they could with a paper map or traditional spreadsheet.
This is important when dealing with big issues like climate change, population dynamics and natural disasters.
Types of Geographic Information Systems
The types of data in Geographic Information Systems, or GIS, include:
- Numeric data — Statistical data collected with a geographic component and displayed as a layer on a map. US Census demographics are an example of numeric data.
- Vector data — Consisting of X and Y coordinates, vector data can describe points, lines or polygons connected to a geographic space. Vector formats are best for data with strict borders, like a street or political district.
- Raster data — Typically digital images in JPEG, TIF or GIF format, raster data is formed from grids of cells or pixels. Satellite imagery is a good example of raster data.
- Linear networks — A layered line that can represent multiple elements, such as a road that is also the boundary of a city or political district.
Sources of Geographic Information Systems
The following are examples of Geographic Information Systems. The GIS data sets are free to anyone, and some are open source GIS:
Natural Earth Data — Download global free GIS data in the public domain, supported by the North American Cartographic Information Society (NACIS).
Esri Open Data — Offers neary 70,000 open data sets from 4,000 organizations. Managed by the largest commercial GIS organization in the world. Download formats in spreadsheet, KML and shapefile. APIs are OGC WMS, GeoJSON and GeoService.
USGS Earth Explorer — Remote sensing data and access to one of the largest databases of satellite and aerial imagery.
OpenStreetMap (OSM) — Crowdsourced data from multiple users that provides highly detailed data with varying levels of accuracy and completeness. High spatial resolution cultural vector data for buildings, land use, railroads, roads and waterways.
Socioeconomic Data and Applications Center (SEDAC) — Provides global socioeconomic data from 15 different themes including: agriculture, climate, conservation, governance, hazards, health, infrastructure, land use, marine and coastal, population, poverty, remote sensing, sustainability, urban and water.
Open Topography — Portal to high spatial resolution topographic data and tools. Offers LiDAR data search in United States, Canada, Australia, Brazil, Haiti, Mexico and Puerto Rico.
United Nations Environmental Data Explorer’s online database — Offers spatial and non-spatial data on freshwater, population, forests, emissions, climate, disasters, health and GDP.
NASA’s Earth Observations (NEO) — Global satellite imagery accessible in JPEG, PNG, Google Earth and GeoTIFF formats.
Terra Populus — Census data of individual and household-level records in 80 countries for the past 60 years.
How Does OmniSci Utilize GIS?
OmniSci makes geospatial capabilities a top priority of our accelerated analytics platform. This keeps the geospatial-specific processes in GIS tools from slowing down with today’s increased data volumes. OmniSci lets geospatial analysts interactively explore up to millions of polygons and billions of mapped points. Business analysts can also easily incorporate spatio-temporal analysis in their regular big data analytics workflows. Learn more about OmniSci for Geospatial Analysts.