A chess opening or simply an opening refers to the initial moves of a chess game. The term can refer to the initial moves by either side, White or Black, but an opening by Black may also be known as a defense. There are dozens of different openings, and hundreds of variants.

Chess opening
Ruy Lopez – Exchange Variation
The Exchange Variation of the Ruy Lopez is a chess opening that begins with the moves: e4 e5 Nf3 Nc6 Bb5 a6 Bxc6 Black may recapture on c6 with either pawn; although 4…bxc6 is playable, […]