WSDL in a nutshell
A WSDL document describes a service:
- message(s) accepted and emitted: abstract description (XML Schema)
- network protocol(s) and message format(s)
- operation: exchange of input and output messages
- interface (previously known as 'port type': collection of operations, now has inheritance)
- endpoint (previously known as 'port': implementation of a port type)
- service: collection of endpoints