The Skybox is a collection of related configurable options that affect the way the environment looks and feels. It includes the texture that surrounds the player's viewpoint, and the level and direction of lighting. It is, in short, what determines what space looks like in Space Engineers. The default skybox makes it look like the player is in a field of asteroids, and is quite convincing at it, to the point that new players may find it difficult to discern which lumps of rock are real asteroids that can be interacted with and the fakes in the "distance". It is for this reason that many players choose to mod their skybox to something less confusing. See List of Mods for some alternate skyboxes.