what is difference between PUT and POST ?

Differences between PUT and POST in REST APIs

Here is the important difference between PUT and POST method:

PUT	POST
This method is idempotent.	This method is not idempotent.
PUT method is call when you have to modify a single resource, which is already a part of resource collection.	POST method is call when you have to add a child resource under resources collection.
RFC-2616 depicts that the PUT method sends a request for an enclosed entity stored in the supplied request URI.	This method requests the server to accept the entity which is enclosed in the request.
PUT method syntax is PUT /employee/{employee-id}	POST method syntax is POST /employee
PUT method answer can be cached.	You cannot cache PUT method responses.
We use  update or replace operation for CURD .	We use  for create  operation  for CURD.
If you send the same request multiple times, the result will remain the same.	If you send the same POST request more than one time, you will receive different results.
PUT works as specific.	POST work as abstract.
We use UPDATE  query in PUT.	We use create query in POST.
In PUT method, the client decides which URI resource should have.	In POST method, the server decides which URI resource should have.