TIME DILATION is what happens between 2 objects when one is moving extremely fast relative to the other.  

      To the stationary observer, anything that happens on the fast moving object appears to slow down, like it's moving through molasses. 

      To a person on the fast moving object, everything back on the planet of departure seems to be sped up like a crazy clock gone haywire.  

      This means that a space traveller in a very fast ship, returning to Earth after what seems like a month's trip at near light-speed, would come back to find that many many years had passed here on his/her home planet; his children would be like grandparents to him, etc. 
      The one thing I'm confused about is, "If all velocity is relative, (as Einstein insists, and after all, Time Dilation is one of his ideas too,) then why wouldn't each person think the OTHER ONE is speeding up, and if that were true, what would they find when they were reunited after the trip?"  

      I'm gonna hafta find out about this....talk to ya later....
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