someone explain this to me please

How is it possible that after I moved 19. g5 my opponent was able to play 20. hxg6?????

Am I missing something here?

http://www.chess.com/livechess/game?id=843288741

It's the en passant rule

what the hell is that

http://en.wikipedia.org/wiki/En_passant

It's a common question we get in support all the time, most people think their computer glitched or their opponent cheated.  It's legit :)

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You have got to be joking, someone explain this to me please

<iframe width="560" height="315" src="//www.youtube-nocookie.com/embed/_-agl0pOQfs" frameborder="0" allowfullscreen></iframe>

explain what ?

Used to be you would use "old embed code" then "preview" your post, then resubmit and it would show up.  Doesn't seem to work anymore.  It must be me, I must be doing something wrong

Hard to believe that posting embedded youtube videos is still an issue here after so long..

http://www.youtube.com/watch?v=_-agl0pOQfs&html5=1