I have some doubt regarding post and get methods, used to process a request... What I understood, that if parameters append with URL then get is used and to send it hidden, post is used... Is there any other specific reason to use get or post except I mentioned above. Please clarify
To me it's more about your intent than their usage. Cryptic, but what I mean is that if you are submitting data, use POST, but if you are sending data to recieve information, use GET.
Examples of the 'POST' type are easy: submitting forms, sending personal info etc. Example of the GET type are things like catalogues, where you send a product ID to a product page to see that product.
It's as much an art as a science, but I saw a reasonable quote here that said GET should be considered idempotent - that is, it doesn't change the state of the server and repeated calls return the same response (with the exception of page trackers etc).