Developing with SOAP

This article will introduce you to what soap is.
SOAP stands for Simple Object Access Protocol
SOAP is a communication protocol
SOAP is for communication between applications
SOAP is a format for sending messages
SOAP is designed to communicate via Internet
SOAP is platform independent
SOAP is language independent
SOAP is based on XML
SOAP is simple and extensible
SOAP allows you to get around firewalls
SOAP will be developed as a W3C standard

SOAP is important because it allows applications to communicate with each other over HTTP - in text formats.
Where as old systems such as Corba could not get round Firewalls, SOAP can send information via the browser.
Its is easy to learn and very extendable just like XML. One application on Windows for instance can easily talk to an application on a Linux or Mac machine.
Soap has been taken on by Microsoft with their .net initiative. Yes Microsoft are doing it again - read Keep your hands off, in my Binary Binge column (development > mxl magazine > binary binge)
Soap 1.1 was not officially supported by the W3C although there was a lot of pressure but they are now developing SOAP 2.0 standards.
Soap messages are built around a few simple building blocks. These make up the soap message.
The soap envelope defines the content of the message, and tells the reader (an application or web page) that it is a soap message.
The soap message also has a header similar to a HTML document that contains important information.
The soap message also has a body tag and this contains the actual message it's self.

This article can be found in the Worfolk Developers Library (Web Developing > XML Web Services > Soap > Soap Introduction)