How to direct an alias to an internal server

I have an internal web server. I would like for people to simply type an alias for the server in their browser instead of the IP to get to it.

Say the server name is ‘foo’ and I want to be able to use the alias, ‘whatever’.

I have Windows Server 2003 R2 acting as a DNS and WINS server. How can I set up the alias so that it redirects internally?

Thanks,

-Travis