what is the fifth pastulate of ???????

plzzzzz... provide a video. i cant understand anything.

 THE FIFTH POSTULATE STATES THAT if a line is drawn randomly between two non-parallel lines,the lines never meet on the side where the interior angles su up to more than 180 degrees and converge on the side where the interior angles sum up to less than 180 degrees..!!

Sorry if i am not clear enough.....i know it is confusing but it requires great talent to explain it in simpler words!!!!