How are n ­type semiconductors and p ­type semiconductors alike. how are they different

 N-type semiconductor materials have been with elements which have spare electrons in their outer shells. This gives N-type silicon free electrons (which are negatively charged partials) which can move about at will - with the potential to create current.

P-type semiconductor materials have been  in the opposite way, with elements that have too few electrons in their outer shells. Therefore the opposite of electrons - holes - are free to move about within the material - with the potential to create current.

You can think of it like positive and negative poles of a magnet.

When you place a piece of N-type silicon next to a piece of P-type silicon, they form a diode. The excess electrons in the N-type are attracted to the excess holes in the P-type, forming what is known as a P-N junction. If you then put a potential difference (voltage) across the junction such that the P-type is sufficiently higher potential than the N-type, electrons will be able to jump across the boarder from the N-type to the P-type, creating current in the opposite direction.
  If you apply the potential difference in the opposite direction, such that the N-type is at a higher potential than the P-type, there is no flow of electrons from the P to the N-type because the N-type already has too many. There is no current flow.


 

Texture and composition are different because they are not the same aspect. texture has to do with feel and so on, where as composition is the chemical makeup which you cant touch like you can texture.