Difference between SOAP (Web Service) and REST Protocols

1.REST has no WSDL interface definition

2. REST is over HTTP, but SOAP can be over any transport protocols such HTTP, FTP, STMP, JMS etc.

3. SOAP is a protocol for sending/receiving data over HTTP as XML. It uses soap envelope over XML , but REST is just XML.

REST(HTTP GET) keeps the state and SOAP is a stateless.
REST is asynchronous.