It is mainly aimed at programming education (object-oriented programming with Java) at high school and early university level.
Greenfoot allows implemention of and interaction with objects in the context of "scenarios". Scenarios can differ widely. Those included with the software download include a lunar lander game, an ants simulation, and turtle graphics. Also available are a lift simulation, Conway's game of life, and an on-screen piano.
Once objects are under development, they can interactively be placed into a Greenfoot 'world', and developers can directly interact with these objects to invoke methods.
Greenfoot is free. Its implementation is based on the BlueJ development environment.
The first full release, Greenfoot version 1.0, was published on 31st May 2006, with further releases following occasionally thereafter.
In May 2007, the Greenfoot project was awarded the "Duke's Choice Award" in the category "Java Technology in Education".
Greenfoot scenarios can be exported to a publicly accessible web site, the Greenfoot Gallery On the Gallery, other web users can play, rate and discuss the scenarios. Source code can also be exchanged via the Gallery.