A web service is an section of software that creates alone available over the web and uses a uniform XML messaging system. XML is employed to encode all communications to an internet service. For example , a client invokes an internet service by sending an XML message, then waits for a corresponding XML response. All transmission is in XML, web services aren’t tied to anybody OS or programming language—Java can talk with Perl; Windows applications can talk with Unix applications. A Web Service are often defined by following ways: It’s a client-server application or application component for communication. The tactic of communication between two devices over the network. It’s a software for the interoperable machine to machine communication. It’s a set of standards or protocols for exchanging information between two devices or application.