"castling"の定義と意味

What is "castling"?

Castling is a special move in chess that involves the king and one of the rooks. The king moves two squares toward the rook, and the rook then moves to the square next to the king on the opposite side. Castling can only be done under certain conditions: neither the king nor the rook involved can have moved previously, there can be no pieces between the king and the rook, and the king cannot be in check or move through a square that is under attack. The purpose of castling is to protect the king by moving it to a safer position, typically behind a row of pawns, while also developing the rook.