Kerbal Space Program is a space flight simulation game. You direct a space program, staffed and crewed by aliens. It looks like a cute game for kids, but under its comic exterior is a hugely complex and engaging space simulation.

To succeed in the game you must work with its accurate simulation of orbital physics to create a spacecraft that is capable of flight and space travel. This allows for orbital manoeuvres as in real space travel, such as Hohmann transfer orbits and bi-elliptic transfer orbits.

Unusually, your task is the administrator of the space program rather than the adrenaline of the flight itself. This not only connects players with the real challenges of space exploration but offers a more sedate and considered experience.

You create the various required craft, rockets, aircraft, spaceplanes and rovers from the provided set of components. You then launch your craft and control it in three dimensions with little assistance. Your aim is to achieve orbit or travel to other celestial bodies, visualised via the map mode that displays the orbit or trajectory of the player vehicle, as well as the position and trajectory of other spacecraft and planetary bodies.

This start is relatively complex, but you can soon get a handle on how the ship builds work. From here though, the complexity can grow as you work out how to create a craft to travel further afield and how to account for orbits and gravity.