Small is beautiful!

Spatial data sets tend to be large, often needlessly so. If you're not using data, keep it compressed: it makes your hard drives go farther.

The popular (shareware) Windows application WinZip can extract data from many popular formats, will create compressed "archives" from files and directories, and is generally a handy tool to have around.

It will "unzip" the usual output of the Unix compression programs:

You will encounter these files as you surf the net for data, and as folks send you data. The "tar" extension implies that a group of files have been "tarred" together to form a "Tape ARchive" - a single file, which WinZip will then have to "expand" to a temporary directory before opening.

Read the WinZip help to find out how to create archives. (Often WinZip is configured so that when you click the right mouse button on a file or directory, an archive will be created - or added to. On my computer, in Windows NT, a right click offers a menu option called "Add to Zip".) Compression is very useful, since disk space is often limited (or expensive). If you're not using files, keep them compressed!

You can unzip all these formats from a UNIX account: IF you're interested, here's how.

Website maintained by Andy Long. Comments appreciated.
aelon@sph.umich.edu