A great post by Clemens in which he does a beautiful distinction between services and web services.
My thoughts would be:
- Service is a self consistent piece of software which MAY use one or more web services for communication with the outside world.
- As always, web services MUST be considered to be within the presentation layer of the solution. They just do not spit HTML out, they prefer XML.
MAY and MUST are to be interpreted as defined in RFC 2119.