The correspondence between host names and IP addresses is maintained in a file called hosts in the (top-level) directory /etc. On most systems, any user can read this file. (A word of caution: on many systems, printing this file may be injurious to local paper supply!!)

Entries in this file look like the following:

127.0.0.1 localhost

192.217.44.208 snoopy beagle hound metlife

153.110.34.18 bugs wabbit wascal

153.110.34.19 elmer

153.110.34.20 sam

Note that more than one name may be associated with a given IP address. This file is used when converting from IP address to host name and vice versa.