Web service Web service allows data exchange in different formats (XML, JSON, text) between Client and Server over the web HTTP protocol. Basic web services are REST and SOAP. REST RE presentational S tate T ransfer is a way / style of implementing a web service of data exchange with following principles: access data by URL based HTTP communication methods GET/POST/PUT/DELETE for actions data can be represented as application/xml, application/json, text/html, etc... request should be stateless, not depending on previous requests, meaning that no information is stored on a server information can be cached on a clint side via Cache-Control & Last-Modified in HTTP Response Headers SOAP S imple O bject A ccess P rotocol uses XML data messages format over HTTP (Post) communication protocol. SOAP is a way of implementing a web service & complies to SOAP Web Services Specifications. Request to be sent in XML format XML format has a defined structure: SOAP MESSAGE SOAP MESSAGE consists from Envelope with Header + Body SOAP vs REST request