Things happen differently from constant moving observers, because speed of light is constant to all frame of reference. Oh, and constant moving observers do not accelerate.
Twin paradox has one of the stuffs accelerating, so its not valid whatsoever it's saying. Anyways...
I remember about a year ago were there was a site that tried to explain the concept of relativity with no word bigger than 5 (or 4) letters. lol even the name "Einstean" was replaced by 4 - 5 letter name. I'll see if i can still find that site.