Types – a container for data type definitions using some

type system

Message – an abstract, typed definition of the data being

communicated

Operation – an abstract description of an action supported

by the service

Port Type – an abstract set of operations supported by one

or more endpoints

Binding – a concrete protocol and data format specification

for a particular port type

Port – a single endpoint defined as a combination of a

binding and a network address

Service – a collection of related endpoints