Web2py is a free and open source web application framework built in Python and designed by Massimo Di Pierro.
The goal of the framework is to make web development easier by focusing on three main goals:
Ease of use
Web2py follows a strict MVC framework where the controls and web templates are all written in pure python. No additional templating language is required.
Many of the features most web applications require are built into every web2py application such as:
User, group and permissions tables
A menuing structure
The DAL or Database Abstraction Layer which allows the user to create schema definitions, which are then translated into database tables in the target database, and form widgets that can be serialized in html templates.
The generated forms provide field validation automatically and the DAL blocks malicious SQL Injections.
Web2py was also built with internationalization features that provide a structured way to deliver applications in a variety of languages.