Divide an object in multiple object

I’m modeling a ship, i started from a cube, extruding it etc and now i need to separate some parts of it, so they can go on different layers.
The problem is that the entire model is considered as an object… how to select faces/vertices/edges and declare them as a new and different object?

Press P in edit mode to separate your selected vertices.

Thanks for the answer… i found it just after i pressed to confirm the new thread… sorry if i asked an already answered question :\