The Simple Object Access Protocol (SOAP) is a
lightweight and simple XML-based protocol that is designed to
exchange structured and typed information on the Web.
The purpose of SOAP is to enable rich and automated Web
services based on a shared and open Web infrastructure. SOAP can be
used in combination with a variety of existing Internet protocols
and formats including HTTP, SMTP, and MIME and can support a wide
range of applications from messaging systems to RPC.