URLs, Routing, and Dispatch

Abstract

All web applications and frameworks need some mechanism for mapping the URL that a user enters in the browser to the code that should be executed when the server receives the request. Different languages and frameworks take different approaches to this. In PHP- or CGI-based systems, the URL represents a path on the hard disk to the file that should be executed. In Zope, URLs are treated as paths in an object hierarchy, and in Django, URLs are matched to code based on regular expressions.