The numerous chess terms and abbreviations can seem pretty complicated and confusing if you are a beginner to chess. But don’t worry, once you get used to them; they will be a breeze!
What Does OO Mean in Chess?
Are you familiar with the term castling in chess? OO refers to a type of castling. So before I get on to explain what 0-0 is and why it is written that way, let me explain what castling is.
Castling is a technique or rule in chess which is used to protect the king. The king is the most important chess piece. If your king is in danger, that means your game of chess is over too. So to protect the king, castling allows you to place the king in a less vulnerable position and surround it with other chess pieces.
Castling means to move your king from its original position two squares towards the rook that is in its original position. And the rook will move two squares toward the king’s original position.
A white king that is e1 will move to g1, and the rook will move to f1.
However, there are a few rules that you must follow when castling.
- The king nor the rook should not have moved from their original position in the first rank.
- You cannot castle if the king is in check.
- There should be no opponent pieces that are blocking the way of the rook or the king.
- The king cannot pass through squares that are being attacked. But interestingly, though, you can castle with a rook that is under attack. A rook can also pass through as attacked square.
- You cannot castle or move your king into check. This rule is easy to remember because it is illegal to move your king into check under any circumstance.
You must also remember that a king will always end on the same color square that is started on when castling. A white king that is on a black square will always end on a black square when castling, and a black king that is on a white square will always end on a white square when castling.
Castling is unique for many reasons. One is that it is the only rule that allows the king to move more than one space. It allows the development of the rook and protects the king at the same time. And it is also the only rule that allows you to move two chess pieces at the same time!
There are two types of castling; kingside and queenside. It is also sometimes referred to as the long side and short side.
Kingside castling or short-side castling has the notation of 0-0, and queenside castling or long-side castling has the notation of 0-0-0. The Os refers to the number of squares the rook has to move. For kingside castling, it moves only two squares, and for queenside, it moves three squares.
Kingside castling is more popular and common than Queenside. I think it’s because it’s easier, and both pieces have to move through less squares.
In queenside castling, the king will move from its original position in e1 to c1, and the rook on the queenside moves to d1.
Why is Castling Important?
Castling serves dual purposes. It protects your king from being exposed to attack and puts it to the side where it is protected by pawns. And at the same time, it allows the rook to develop early in the game. The rook’s range of movement makes it very useful if it is in a central position.
Castling also allows your rooks to ‘chat’ or communicate with one another. They have open ranks between them, and castling allows them to patrol the ranks freely, protecting the other chess pieces.
Since your rook can castle even when under attack, this could also be a ploy to save your chess pieces. It’s always best to castle early in the game but also not too early. Wait till your opponent has committed to the game before you castle so that it can potentially disrupt their strategies.
So, in conclusion, what does OO mean in chess?
OO refers to kingside castling. Castling is the movement of both the rook and the king at once. In kingside castling, the king moves two spaces toward the rook, and the rook moves two spaces toward the king’s original position. Castling protects the king from attack and allows the rook more freedom of movement.
Also read: How common is castling in chess?