A service offered by an electronic device to another electronic device, communicating with each other via the Internet. In a web service, a web technology such as HTTP is used for transferring machine-readable file formats such as XML and JSON.

In practice, a web service commonly provides an object-oriented web-based interface to a database server, utilized for example by another web server, or by a mobile app, that provides a user interface to the end-user. Many organizations that provide data in formatted HTML pages will also provide that data on their server as XML or JSON, often through a Web service to allow syndication.

W3C definition

Software system designed to support interoperable machine-to-machine interaction over a network. It has an interface described in a machine-processable format (specifically WSDL). Systems interact with the web service in a manner prescribed by its description (WSDL) using SOAP-messages, typically conveyed using HTTP with an XML serialization in conjunction with other web-related standards.

Webservices is XML-based language-independent communication protocol which supports:

  • Remotely executing methods
  • handling errors
  • authentication/authorization

See also Java Webservices.