In very simple words, WS is Web based service
Web - Because services use HTTP as the protocol to communicate
Service - A independent system/program/unit (whatever you name it) that gets some logical work done
Relating that to the real world, a service provider is some one that provides some service (think toeing service for example). You find this provider from a registry (yellow pages for example) and use your voice as the communication protocol to call the provider, the toeing guy tells you what he does, how and his charges and you use him if you agree.
Going back to the software world, think of services as programs that do some work (authentication, credit card authorization, money transfer). If your application needs any of these services, you find them in a registry (UDDI), understand what they offer, how and what you need to send them (WSDL) and then use the service by invoking say credit card authorization (
SOAP).
From your signature, it looks that you are quite familiar with programming, so in coding terms, arguably, a method or a function is an abstraction, a calss is higher level abstraction, a component (an
EJB) is at higher level than that and a WS is even higher level of abstraction.
I will leave it up to you to use the links provided by the previous poster to understand the acronyms I used and recognize the benefits of this concept. Also, understand the role of xml in implementing the WS.
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