Does somebody know how I can translate an ip-address on a Macintosh computer???

so, if i use 'myName' in the internet explorer, the mac can't find the ip-address.

But if i type the ip-address, he finds the intranet-site.

How can I make a kind of 'hosts' file, so that he knows that 'myName' equals ip-address '10.10.0.15' ???


I hope someone can help?
Thanks, Calle.