Mostly, there are two kinds of Web Services which are quite popular.
1. SOAP (Simple Object Access Protocol) which is an XML-based way to expose web services.
2. Web services developed using REST style are known as RESTful web services. These web services use HTTP methods to implement the concept of REST architecture. A RESTful web service usually defines a URI, Uniform Resource Identifier a service, provides resource representation such as JSON and set of HTTP Methods.
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