You config may include public, private, or otherwise non-public addresses. If there are public addresses or names that resolve to your public addresses, you may wish not to publish them or to mask them, especially if you are posting about configuration problems that could be abused. However, that can also hinder people from helping you, of course.
Usually a computer in a home behind a box will be NATed, and thus only have private IPs, but you might have a hosted server with a public IP.
The following are common addresses that everyone and anyone can have in their configurations, they are safe to publish:
- 10.0.0.0/8 (10.0.0.0 - 10.255.255.255): RFC1918 "A" private
- 127.0.0.0/8 (127.0.0.0 - 127.255.255.255): localhost
- 172.16.0.0/12 (172.16.0.0 - 172.31.255.255): RFC1918 "B" private
- 169.254.0.0/16 (169.254.0.0/16 - 169.254.255.255): link local
- 192.168.0.0/16 (192.168.0.0 - 192.168.255.255): RFC1918 "C" private
- ::1/128 inet6 localhost
- inet6 link-scope addresses
There are other special addresses, but most people will not have them in their configurations without knowing very well what they are. All special addresses are listed in RFC6890.
For any address, you can consult the IANA list which will give you the Regional Internet Registry if applicable, and the whois server which will give you more information on the range in question. For a public IP address you will certainly be able to drill down to your ISP.
To know your public IP address, search google for "what is my IP address".