Once you modify the publication you repeat the publish process. Publisher
then writes new site files to replace previous ones.
Version 2003 introduced the optional Incremental Upload which reduce how
many files are actually over-written.
See http://www.publishermvps.com/Default.aspx?tabid=164 and also
http://office.microsoft.com/en-us/assistance/HA011187871033.aspx

Signature
David Bartosik - [MSFT MVP]
http://www.publishermvps.com
http://www.davidbartosik.com
> If I publish a website using Publisher and then want to update something, do
> I have to re-publish the whole site or is their an easier way to do updates?