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What is metadata and why is it important?
"Metadata is a 'list of ingredients and procedures' that describes the overall product whether it be a cake or nuclear reactor. End-users need to know what the ingredients are and how they were combined so they can tell if the cake will be good to eat or have ingredients that allergy sufferers should be aware of. It also lets the user know how accurately the procedures were followed and the quality of the end product - is it safe to use?"
Richard Chaney
"Metadata should be structured in a Federal Geographic Data Committee (FGDC) manner. There are numerous documents on the Web and embedded within various software packages that will enable a user to create metadata. Metadata can be saved in a word document, HTML, XML, or standard text file."
Learon Dalby
"Global Positioning System (GPS) is a constellation of high orbit satellites operating in tandem with a ground receiver that can interpret earth-based locations." Please visit http://www.gis.state.ar.us/ASLIB/AnnceGPS.htm for information about Arkansas Global Positioning Standards.
Shelby Johnson
"The geoTIFF file format embeds image registration information directly into the raster file. GeoTIFF is an industry-neutral raster file format widely used and recognized by all of the major GIS software vendors."
Learon Dalby
"A projection is a mathematical model used to define 3-dimensional earth space onto a flat plane."
Shelby Johnson
"A datum is a mathematical model used to determine overall height of continental land masses like North America. A common datum is the North American Datum of 1983, more commonly known as NAD83."
Shelby Johnson
Why do projection and datum matter?
"When a person uses the measurement tools found in most GIS systems to measure coordinate location, distances, or areas, the result is an improved answer; therefore, both of these mathematical models matter."
Shelby Johnson
"While there are many sources of information on coordinate systems, datum, and spheroids, the U.S. Geological Survey has produced some thorough documentation on their Web site. Visit these links for more information: http://webgis.wr.usgs.gov/map_projs.htm and http://mac.usgs.gov/mac/isb/pubs/MapProjections/projections.html."
Vince Guillet
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