During Microsoft's keynote speech at CES, a 12-year old girl named Sparrow created a virtual environment on the Xbox 360. It was the first public glimpse of Kodu, a new tool for building game worlds.

Nothing new about that you might think. LittleBigPlanet on the PlayStation 3 already offers sandbox world-building.

Watch the CES demo video and you'll see that Kodu is arguably more flexible. It's essentially an object orientated programming language that enables players to build virtual playgrounds and, ultimately, their own simple games.

Visual building blocks

Once an environment has been constructed in Kodu, players can populate it with over 200 visual building blocks. These objects – vehicles, trees, houses, rocks, etc. – are endlessly programmable, so they can be given rules. These rules can then be strung together into behavioural patterns.

As Microsoft explains it: "Kodu-created playgrounds are expressed in physical action-reaction terms, using basic concepts like vision, hearing and time to control your character's behaviour."

During the CES demo of Kodu, Sparrow had created a simple two-player game. It involved guiding a UFO around to find rocks, collecting the rocks before the other player and then delivering them to a house to score points.

In programming terms, this involves defining how a player controls the UFO, what button picks up a rock and releases a rock, and that 10 points are scored if the rock is released next to a house.

DIY game development

Kodu encourages logical thinking. The software was originally designed by Microsoft Research as a learning tool for young kids. But it has the potential to resonate with the youth market more than Viva Pinata ever could.

"We've done everything possible to make sure that creating a Kodu playground is not only easy, but that it is also fun and engaging for people of all ages and backgrounds," said Matt MacLaurin, the principal program manager for Microsoft Research.

"Since Kodu's interface is intuitive and prevents common programming mistakes, we're making it easy for everyone to enjoy the magic of game creation."