JMeterLecture 25 JMeter REST API and SOAP API Testing
Both REST and SOAP are web services. But SOAP is defined as Simple Object Access Protocol. It only works with XML for response data formatting. So, if you see a description for a web service that does not use XML for the response data format, it is not SOAP.
REST works with plain text, XML, HTML and JSON formats. The most common response data format for REST is JSON. REST is a more flexible web service and, in more demand, today.