REST vs Client Server

Inspired by the discussion between WSDL and REST from Cedric and Philip, I decided to have a close look at the REST.

REST at Wikipedia explains REST in very detail, but a newbie like I won't be able to understand what it is at the first look. Alternatively I found Building Web Services the REST way written by Roger Costello is a very good read.

REST is a design architecture instead of a standard such as WSDL. Costello suggests viewing REST as Client-Server, a well-known architecture but there is not such a standard named Client-Server. So is REST. Now I think I get it. :-)