So, I know the definition of json, I know its a lightweight data format.
As I am not an expert on this subject I would like to know, when can I use JSON, in which scenarios or applications? How to do it in c#?
I suppose I would Use Json only in applications where I intend to use ajax?
I use Json to call web service methods only so that I can use javascript to show the results without a postback?
Is JSON something to be used only in web forms applications? asp.net mvc applications? silverlight? winforms?
Well, you ask too many questions. My personal view on JSON:
1) JSON is a good tool if you need to deal with AJAX (as Sietse pointed out it should be called AJAJ in this case) and webservices
2) JSON is a good tool if you generally need to communicate between different platforms. I used it for communication between PHP and C# program because JSON is implemented in so many languages it is natural to use it and avoid creating custom communication procotol.