GIS is defined as an:
Acronym for Geographic Information System--an integrated collection of computer software and data used to view and manage information about geographic places, analyze spatial relationships, and model spatial processes. A GIS provides a framework for gathering and organizing spatial data and related information so that it can be displayed and analyzed.
[URL:http://resources.arcgis.com/glossary/term/533. Accessed: 2010-05-19. (Archived by WebCite®at http://www.webcitation.org/5pqO1iWZ4)]
GIS is used in engineering, environmental science, land surveying, urban planning, emergency management, business intelligence, and Web mapping applications. As GIS becomes more mainstream, more applications and uses are being introduced. As society becomes more mobile, GIS and GIS applications are finding their way to smartphones, tablet PCs, and other Wi-Fi connected devices.
Applications make up the heart of a GIS. These applications are used to edit data, create queries on data, model and analyze geospatial relationships, and create and display maps. Web-based applications such as Google Earth have revolutionized how we edit, view, and display geospatial information.
The following Penn State video (5 minutes) gives you a good introduction to GIS, its uses, and capabilities.
KASS GREEN, American Society for Photogrammetry & Remote Sensing: Say you're in California, where I live, and you want to know how susceptible your house is to a wildfire.
So we put sensors, like our eyes, on satellites. We collect information, and then computers create maps. OK, now you have a map, so you want to analyze that map. Well, you'll take the information about the slope. Are you on a dead-end street? Do you have a lot of fuel around your house? You put all that information into a computer. And it can tell you how at risk you are for losing your home to a wildfire.
MARK BRENDER, GeoEye: Ever since the Babylonians etched the lay of the land on clay tablets in 2300 BC, mankind has needed accurate representations of the earth.
KASS GREEN: Maps used to be made on horseback in the 1800s. They took a long time to make, so we evolved to aerial photography, and that's made a huge difference with how humans understand the earth.[PILOT'S VOICE]
JACK DANGERMOND, ESRI GIS & Mapping Software: In the '60s, people began to think about the notion of encapsulating or abstracting geography in a computer. And people could look at the database and visualizations or analytics. And that was just a magical idea.
PRESIDENT OBAMA: I, Barack Hussein Obama, do solemnly swear that I will preserve, protect, and defend the Constitution of the United States.
CHIEF JUSTICE ROBERTS: So help you God?
PRESIDENT OBAMA: So help me God.
CHIEF JUSTICE ROBERTS: Congratulations, Mr. President.
: The Obama campaign took to a new level their use of technology with respect to mapping.
KASS GREEN: They knew what voters to target. They knew where the marginal voter was. And, frankly, the ones that use it the most effectively get elected.
MARK BRENDER: After 9/11, US troops went into Afghanistan, and they went in with Russian maps because who would ever think you'd have to have maps of Afghanistan.
VICE ADMIRAL ROBERT MURRETT: Geospatial intelligence has become really the foundation for just about anything that happens in the military. It has to do with understanding in a very time-sensitive fashion things that may be developing in different parts of the world.
HON. JAMES R. CLAPPER: It's the ability to enable decision makers, whether they're someone sitting in the White House or someone sitting in the foxhole.
MARK BRENDER: More than half the world's population now lives in urban areas. Thirteen of the 20 largest cities are on coastlines. So how do you model in potential rise of sea level because of climate change?
RICHARD ALLEY, Geoscientist, Nobel Prize Winner, Penn State: We simply could not know how the earth works without geospatial technologies telling us where things are, how they're related, how it's put together to tell us the story of what really is happening.
SCOTT EDWARDS, Amnesty International: The conflict in Darfur is over five years old now. Somewhere around 400,000 people have died. We wanted to go to the place, collect testimony, take photographs. The Sudanese government had very little interest in having us on the ground. So we purchased satellite imagery, and we saw whole villages destroyed. We took those images to the Sudanese government to let them know that people around the world were watching these villages remotely.
DAVID DIBIASE, Mapping Scientist, Penn State: For the insiders, the transition to digital geography has been truly revolutionary. We can navigate our world with much greater confidence then we could have before. It's changed the science agenda. It's changed the technology. It's created new occupations. But for those outside, who may not even be aware that there is a field called geospatial, it has made geography ordinary, which is the most revolutionary thing of all.
Other definitions of GIS have also been offered as alternatives. Review example definitions collected by Kenneth E. Foote and Margaret Lynch from the Department of Geography, the University of Texas at Austin.
USGS defines GIS as "... a computer system capable of capturing, storing, analyzing, and displaying geographically referenced information; that is, data identified according to location. Practitioners also define a GIS as including the procedures, operating personnel, and spatial data that go into the system.