What is long castle vs short castle?

Long castle and short castle are two basic types of castling moves in chess. Castling is a move made by the king and either rook of the same color, where the king is moved two squares towards the rook, and that rook moves to the square over which the king crossed.

Long castle refers to when the king moves two squares to the left and the rook moves to the square immediately to the right of the king. This move is denoted as O-O-O on the chessboard notation.

Short castle, on the other hand, is when the king moves two squares to the right and the rook moves to the square immediately to the left of the king. This move is denoted as O-O on the chessboard notation.

The decision to long castle or short castle usually depends on the position of the pieces and the player's strategy. Long castle is generally considered to be a safer option as it provides the king with additional protection due to the distance between the king and the opponent's pieces. However, it also takes a longer time to execute, and the rook may be relatively passive in the game. Short castle, on the other hand, is a quicker move, and the rook can be more actively involved in the game. However, the king's position may be more vulnerable due to its proximity to the opponent's pieces.