I have several items that are allowed in the built in security firewall, but some of their names make them seem suspicious. httpd, krb5kdc, named.
All the others are for applications I use. *Do I need them and what are they used for? I'm running a new macbook with OS 10.6. In the advanced firewall settings I only have the enable stealth mode checked.
More aboutwhat shown firewall
httpd = Web Server krb5kdc = Kerberos authentication named = DNS Server
You probably want the second one; whether you want the first and last is up to you.
Google would have solved this for you, and allow you to find out more about all these services.