Running through a gateway at
http://yourserver/cgi-bin/script
the request using PATHINFO .html would be
http://yourserver/cgi-bin/script/foo.html
PATH_INFO= /foo.html
PATH_TRANSLATED= /var/web/htdocs/foo.html
while
http://yourserver/cgi-bin/script/baz/bar.html
PATH_INFO= /baz/bar.html
PATH_TRANSLATED= /var/web/htdocs/baz/bar.html
The advantage is that the server will do user-dir escaping for you, so
http://yourserver/cgi-bin/script/~baz/bar.html
PATH_INFO= /~baz/bar.html
PATH_TRANSLATED= /u/baz/public_html/bar.html
This makes it easy to open the files and process them in the script.
Check http://www-pcd.stanford.edu/mogens/script.html for an example
of path_info use.
Christian