“Chess960 is healthy and good for your chess. If you get into it and not just move the pieces to achieve known positions it really improves your chess vision.”
— Levon Aronian
Chess960 (also known as Fischer Random) is a chess variant where the starting position of each piece in the home rank is randomized. However, the pieces of both sides will still be symmetrical.
All the rules of standard chess apply. In particular, pieces work as if in standard chess, with the exception of castling.
Castling is legal in Chess960. Here's how it works:
In all 960 starting positions of Chess960, the pairs of rooks will always be on different sides from the king, so it is always possible to castle both kingside and queenside. Additionally, both bishops will be placed on opposite colored squares.