Why does a web server need to know the address, browser type, and cookies for a requesting client?

Reasons why a web server needs to know the address,browser type and cookies for a requesting client are
i)address-to send back requested pages/files
ii)browser type-this is because different browsers render differently and support different functions so they may require different versions of files.
iii)cookies-they use cookies to track session and user information.Thus without a cookie the server cant know the context of the request.

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