[newbie] Is my hosts.deny working??

[ai4a]

Hi:
I use my system as a simple desktop machine & connect to the internet
through a ppp line & a 56K modem. Does this mean that I connect to the
internet and no one needs to connect to me??

In my hosts.deny file I have:
  ALL: ALL: DENY

In my hosts.allow file I have nothing:
# there are no entries in my hosts.allow file

I can still connect to the internet and all works fine. Is my hosts.deny
file working? Do I have a deamon turned off? How can I test if
hosts.deny is working?