newbie question

Blitz3D Forums/Blitz3D Programming/newbie question

i would have posted in 'beginners' but it's defn. 3d related...

what's the difference between a world editor and level editor? some terrain editors seem to allow you to place objects, wouldn't that then be equivalent to a world editor?

what is a lightmapper for? what is a lightmap, when do you load that, what is it for?

and finally, what's the deal with shadows, why would i need a 'shadow system'? do lights not cause shadows to happen automatically?

slightly confused newbie!

(is there a beginners overview somewhere??)