Geo Communities :: Basic GIS information, such as what it is, how it works, and what the components are.

LIGIS (Long Island Geographic Information Systems) :: The "Long Island GIS" User Group keeps you up to date on GIS activities in Suffolk County. Find out when the next informational meeting is, browse their archived newsletters, and explore their interesting links.

GIS Day :: Learn more about GIS Day (November 16th) and what you can do to participate!

Back to Basics :: Developed by GISDevelopment.net, it gives a basic overview of GIS and its applications. It is not software specific.

"The GIS Primer" :: By David J. Buckely of the Pacific Meridian Resources Inc. It is a more advanced look into GIS, providing an overview of issues and requirements for implementing an effective GIS program.

United States Geological Survey :: A more detailed overview of basic GIS information and its applications. Many images are included so this visually demonstrates how GIS works. It is not software specific.

GIS Self Learning Tool :: Developed by the University of Melbourne (Department of Geomatics), this tool covers a range of subjects that covers both introductory and advanced topics. It is not software specific, but shockwave is required for the interactive components.

Numerous "data viewers" exist which are available at no cost over the internet. These can be utilized for viewing various data layers, such as streets or water bodies, which can also be downloaded. Unless you already have data in ESRI or MapInfo format, I recommend the TatukGIS Viewer since it is able to view data in many GIS formats.

ArcExplorer :: A lightweight data viewer developed by ESRI; one of the leading GIS software developers. ArcExplorer allows you to perform basic GIS functions such as display, query and data retrieval applications. Compatible with ESRI file formats such as shapefiles (SHP).

ProViewer :: A basic data viewer developed by Mapinfo, also one of the leading GIS software developers. Proviewer allows you to display and manipulate data. It is compatible with MapInfo file formats (TAB, MIF/MID).

TatukGIS Viewer :: A data viewer developed by TatukGIS. The viewer allows you to perform many commonly used GIS functions such as displaying and querying data, and is compatible with many GIS file formats including ESRI and MapInfo.

A significant number of GIS layers are freely available for download from the internet. It is possible to overlay coastal and municipal boundaries, roads, wetlands, topographic maps and even aerial photographs. Careful attention should be paid to the format of the data however, since some viewers can only read data of a specific type.

LIGIS (Long Island Geographic Information Systems) :: Provides basic start-up for Long Island including layers showing: coastline, town and municipal boundaries, railroads and major roads. Data is in ESRI format.

CUGIR (Cornell University Geospatial Information Repository) :: Once "Suffolk County" is selected, you can choose from many different layers including: roadways, census data, wetlands and agricultural districts.

AGI Dictionary :: A comprehensive on-line dictionary of GIS terms provided by the Association for Geographic Information (AGI).

ESRI Dictionary :: A comprehensive listing of GIS definitions provided by the ESRI Support Center.