Help setting up a remote desktop connection

[Achiever]

I work in an office that is a PC environment (I know, I know...) and the tech guy has been setting up people's work computers to allow them to access files off of our servers remotely to enable us to work from home without emailing documents, bringing files home, etc. He emailed employees instructions on how to set up their home computers to make this work...but his instructions involve using the Windows Remote Desktop client. I have advised that I have a Mac which does not - and will not - run Windows on it for any reason and he responded that OS X has a built in remote desktop client which can be used. Unfortunately, he had no further info for me than that.

Can anyone here tell me what the Mac equivalent is to the Windows Remote Desktop client and how the installation on my Macs would differ from Windows instructions he has given me (essentially, input a specific series of numbers in the "Computer" field of the WRDC, check the box "Allow to save credentials", set the Save As in the Connections Settings and click Connect.). Thanks in advance.

EDIT: BTW, I am on 10.6, they are on Windows XP, if any of that makes a difference.