What is REST and what is SOAP?
Representational State Transfer (REST) is a software architecture style for building scalable web services. REST services typically communicate via HTTP and are built using XML and JSON.
Simple Object Access Protocol (SOAP) is a protocol specification for exchanging structured information to implement web services. It uses XML Information Set for message format and other application-layer protocols, such as HTTP or SMTP for message transmission.
REST is far more common of the two types of service, as it is more flexible (permitting more data formats, while SOAP only allows for XML) and uses standard HTTP. RESTful reads can also be cached, while SOAP reads cannot.
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