In Java, the term "URL rewriting" sometimes describes a Web Application Server adding a session id to a URL when cookies are not supported (e.g. "index.jsp" is rewritten to "index.jsp;jsessionid=xyc" when the links are drawn in an HTML page).
^ Many of these only apply to HTTP servers whose default behavior is to map URLs to filesystem entities (i.e. files and directories); certain environments, such as many HTTP application server platforms, make this irrelevant.