A Web service is defined by the W3C as "a software system designed to support interoperable Machine to Machine interaction over a network." Web services are frequently just Web APIs that can be accessed over a network, such as the Internet, and executed on a remote system hosting the requested services (source: Wikipedia) •Web services are application components
•Web services communicate using open protocols
•Web services are self-contained and self-describing
•Web services can be discovered using UDDI
•Web services can be used by other applications
•XML is the basis for Web services
Web Services have three basic platform elements: These are called SOAP, WSDL and UDDI. We will explain these topics later in the tutorial
The basic Web services platform is XML + HTTP.
The HTTP protocol is the most used Internet protocol.
XML provides a language which can be used between different platforms and programming languages and still express complex messages and functions. A few years ago Web services were not fast enough to be interesting. Thanks to the major IT development the last few years, most people and companies have broadband connection and use the web more and more. Web services have two types of uses:
Reusable application components
There are things different applications needs very often.
Web services can offer application components like currency conversion, weather reports or even language translation as services. Ideally, there will only be one type of each application component, and anyone can use it in their application. Connect existing software
Web services help solve the interoperability problem by giving different applications a way to link their data. Using Web services you can exchange data between different applications and different platforms.