Decoration (noun). specifically, any mark of honor to be worn upon the person, as a medal, cross, or ribbon of an order of knighthood, bestowed for services in war, great achievements in literature, art, etc. Origin: [LL. decoratio: cf.
A P-N junction (or N-P junction) is formed by creating two substrate materials of P type and N type on a semiconductor. P type means it is doped with free holes (electron depletion) and the N type is doped with electrons. Of course by physics, the free holes and free electrons would like to neutralize each other.
P.S. is short for postscript, which is defined as an addition to a letter. An example of P.S. is what a person writes after his signature in the letter if he forgot to include something in the body. ps. PS.