Click on the initialize button to start the demo.

This is an old viewer, but it is still an excellent way to learn MapServer CGI mode, and also display accurate MapServer scale values, to use in your mapfile. Just modify this mapfile to include your own data: \ms4w\apps\cgi-viewer\map\cgi-demo.map

The data and mapfile was put together originally by Jeff McKenna back in 2001 !