I use the excellent Firefox extension LiveHttpHeaders for this. It also shows the request headers and the response status code.
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Joined: Oct 30, 2007
I would like to know the headers that we mention in the document,where are they validated or how,where and when the execution of the headers take place?
Joined: Mar 22, 2005
I don't understand what you're asking. What is "the document"?
Also, headers aren't "executed", they may be read by the receiving side, and sometimes they're used for making decisions on how to send the response. Obviously, the latter applies to request headers only. The most important purpose response headers are used for are probably content length and encoding, and setting cookies.
Are you asking about some specific header, or in the context of some specific issue?