What is SOAP? – SOAP is a specification for using XML documents as messages. The SOAP Specification contains:
[1] A syntax for defining messages as XML documents, referred to as SOAP messages.
[2] A model for exchanging SOAP messages
[3] A set of rules for representing data within SOAP messages, known as SOAP encoding
[4] A guideline for transporting SOAP messages over HTTP
[5] A convention for performing remote procedure calls (RPC) using SOAP messages