Abstract: A system for enabling a user of a computer attached to a computer network, and accessing sites on the network, to manage user-characterizing protocol headers on the user's computer. A particular application of the present invention is to manage so-called Internet cookies on a computer attached to the Internet and using a browser to access websites through the World Wide Web. Such cookies have a type and a value. The managing includes displaying to a user an interpretation of cookies that have been set on the user's computer; the interpretation is made by an interpreter referring to a local cookie dictionary, on the user's computer, having entries corresponding to different types of cookies. In various alternative embodiments, the managing also includes changing the values set by the websites, and fabricating cookies of types not necessarily used by a website in order to express to the website preferences a user wants the website to know.