What do you mean by Web Service?

The term Web services describes a standardized way of integrating Web-based applications using the XML, SOAP, WSDL and UDDI open standards over an Internet protocol backbone.

• XML is used to tag the data
• SOAP is used to transfer the data
• WSDL is used for describing the services available
• UDDI is used for listing what services are available

Used primarily as a means for businesses to communicate with each other and with clients, Web services allow organizations to communicate data without intimate knowledge of each other's IT systems behind the firewall.