doc for Frameworks, WSGI, Django, Flask

docs/scenarios/web.rst

@@ -9,18 +9,67 @@ Context
 WSGI
 ----
 
+The Web Server Gateway Interface (or "WSGI" for short) is a standard
+interface between web servers and Python web application frameworks. By
+standardizing behavior and communication between web servers and Python web
+frameworks, WSGI makes it possible to write portable Python web code that
+can be deployed in any `WSGI-compliant web server <#servers>`_. WSGI is
+documented in `PEP-3333 <http://www.python.org/dev/peps/pep-3333/>`_.
+
 
 Frameworks
 ::::::::::
 
+Broadly speaking, a web framework is a set of libraries upon which you can
+build custom code to implement a web application (i.e. an interactive web
+site). Most web frameworks include patterns and utilities to accomplish at
+least the following:
+
+URL Routing
+  Matches an incoming HTTP request to a particular piece of Python code to
+  be invoked
+
+Request and Response Objects
+  Encapsulate the information received from or sent to a user's browser
+
+Template Engine
+  Allows for separating Python code implementing an application's logic from
+  the HTML (or other) output that it produces
+
+Development Web Server
+  Runs an HTTP server on development machines to enable rapid development;
+  often automatically reloads server-side code when files are updated
+
 
 Django
 ------
 
+`Django <http://www.djangoproject.com>`_ is a "batteries included" web
+application framework. By providing many utilities and patterns out of the
+box, Django aims to make it possible to build complex, database-backed web
+applications quickly, while encouraging best practices in code written using
+it.
+
+Django has a large and active community, and many pre-built `re-usable
+modules <http://djangopackages.com/>`_ that can be incorporated into a new
+project as-is, or customized to fit your needs.
+
+There are annual Django conferences `in the United States
+<http://djangocon.us>`_ and `in Europe <http://djangocon.eu>`_.
+
 
 Flask
 -----
 
+`Flask <http://flask.pocoo.org/>`_ is a "microframework" for Python. Rather
+than aiming to provide everything you could possibly need, Flask implements
+the most commonly-used core components of a web application framework, like
+URL routing, request and response objects, and templates. As a user of
+Flask, it is therefore up to you to choose and integrate other components
+you may need, such as database access or form generation and validation. For
+many popular modules, `Extensions <http://flask.pocoo.org/extensions/>`_ may
+already exist to suit your needs.
+
 
 Pyramid
 -------