When you find a file with a .gz, .zip, and/or tar extension, it has been compressed .  You can uncompress the file with the WinZip utility.  Winzip can be downloaded from the WinZip web site.

Once installed, to uncompress a file you can go to that file on Windows Explorer or File Manager, place the mouse cursor over the compressed file, then click on the right mouse button.  Choose one of the "Extract to..." choices - this will uncompress the file(s). For GIS purposes, I typically choose the extraction option that extracts to a new folder of the same name as the zip file (e.g., urban246.zip will be unzipped into a new folder called "urban246").

11 September 2001
The School of Architecture at UT Austin
Comments to: Barbara Parmenter