How do you O-O

Hello, I was wondering if you could explain to me how to castle King-side/Queen-side. Thank you everyone. 

On the off chance that you're serious: 

Castling

One other special rule is called castling. This move allows you to do two important things all in one move: get your king to safety (hopefully), and get your rook out of the corner and into the game. On a player’s turn he may move his king two squares over to one side and then move the rook from that side’s corner to right next to the king on the opposite side. (See the example below.) However, in order to castle, the following conditions must be met:

• it must be that king’s very first move
• it must be that rook’s very first move
• there cannot be any pieces between the king and rook to move
• the king may not be in check or pass through check

1. O-OO-O-O

–X

f

J#,.@

Notice that when you castle one direction the king is closer to the side of the board. That is called castling kingside. Castling to the other side, through where the queen sat, is called castling queenside. Regardless of which side, the king always moves only two squares when castling.

Sigh....Just once I wish I could get a copy and paste to work.   Luckily the diagram links to the original article where the pieces are correct.  Sorry about that.

Move your king first.

His name is interesting eh?

He can change it once if I'm not wrong, probably he'll pick En_passant for the next one.

or Resignation.

Why does the move EXIST though? How is it allowed? I know it is, but why? And yeah, I know I'm like 7 years late to the conversation, but I want to know.

@8

Originally in chaturanga the queen (vizier) was a weak piece.
When the queen was made stronger, also castling was introduced to offset that.

Likewise pawns originally in chaturanga could only make one step.
When pawn moves of 2 steps were introduced, also en passant was introduced to offset that.

The reason that castling is called O-O is:

That's your eyes popping out when you first see somebody play this move.

And O-O-O is when your eyes pop out AND you shake your head in chagrin.

Bleb

Bleb indeed.

Move the king first..    smiONE

a example of castling 

Nice