Mention what is the difference between PUT and POST?

PUT puts a file or resource at a particular URI and exactly at that URI. If there is already a file or resource at that URI, PUT changes that file or resource. If there is no resource or file there, PUT makes one.

POST sends data to a particular URI and expects the resource at that URI to deal with the request. The web server at this point can decide what to do with the data in the context of specified resource

Mention what is the difference between PUT and POST? (Cont...)

PUT is idempotent meaning, invoking it any number of times will not have an impact on resources.

However, POST is not idempotent, meaning if you invoke POST multiple times it keeps creating more resources.