Here i wana to add some basic stuff:
Agreed , its a ways by which your published application can be accessed accross the world and across the platform.
In short and more meaning full, its a programmable application which is accessiable via Standard Web Protocol and one of the web protocol is SOAP.
AS we know main two attributes of Web service is XML+HTTP.
SOAP use XML for data description and HTTP for tranporting your data.
I must say, SOAP work as an envolape which cover over messages and send and receive by different transport based on the address .
in the world of technology, this webservices help users to send and receive the information without any barrior of languages and platform.
Consumers of a Web Service do not need to know anything about the platform, object model, or programming language used to implement the service; they only need to understand how to send and receive SOAP messages (HTTP and XML).