I want to know on all possibilities of HTTP Verbs.
These were few questions I was asked in a interview.
Apart from these, are there any other tricks or tweaks, that can be done in web api action method to make them perform operations other than what it is meant to?
The HTTP verb is essentially another piece of the puzzle when it comes to deciding which action method to invoke on a controller, alongside the route definition.
There is obviously convention about how each verbs should behave and be used, but once you end up in an action method you are free to do whatever you want.
You could create a record from a GET or even a DELETE and you can certainly return data from a POST. Back to the convention point though, you generally would not expect to receive data in the body of a GET request for example, and this means providing sufficient data to create something may become unwieldy if you want to pass it all in the URL or query string.