In knoppix ( 2003-04-28 ) after hd install if I run ShieldsUP! site to test ports

http://grc.com/x/ne.dll?rh1ck2l2

It finds that Port 80 HTTP service is open.

what is keeping this port open? how to shut it?

I´m not in a local net. My box is a single workstation.

Any ideas?
Thanks