SOAP vs. REST

SOA standards typically include SOAP as the service messaging standard consisting of WSDLs and XML.  A standard was needed so the industry worked out a multi-step, description-based solution involving XML. 

Along came REST (Representational State Transfer) where everything has a resource URI and actions (CRUD - Create, Read, Update, and Delete) are controlled by verbs (Post, Get, Put, and Delete - respectively).