Ruy Lopez Chess Opening

The Ruy Lopez, called the Spanish Opening or Spanish Game outside of English speaking countries, is a chess opening characterised by the moves:

1.e4 e5
2.Nf3 Nc6
3.Bb5
The Ruy Lopez is one of the most popular openings. It has such a vast number of variations that in the Encyclopaedia of Chess Openings all codes from C60 to C99 are assigned to them.

History
The opening is named after the 16th century Spanish priest Ruy López de Segura. He made a systematic study of this and other openings in the 150-page book on chess Libro del Ajedrez written in 1561. However, although it is named after him, this particular opening was known earlier; it is included in the Göttingen manuscript, which dates from around 1490. Popular use of the Ruy Lopez opening did not develop, however, until the mid-1800s when Carl Jaenisch, a Russian theoretician, "rediscovered" its potential. The opening is still in active use as the double king's pawn opening most commonly used in master play; it has been adopted by almost all players at some point in their careers and many play it from both the white and black sides.

Basics
At the most basic level, White's third move attacks the knight which defends the e5 pawn from the attack by the f3 knight. It should be noted that White's apparent threat to win Black's e-pawn with 4.Bxc6 dxc6 5.Nxe5 is illusory — Black can respond with 5...Qd4, forking the knight and e4-pawn, or 5...Qg5, forking the knight and g2-pawn, both of which win back the material with a good position. 3.Bb5 is still a good move, however: it develops a piece, prepares castling, and sets up a potential pin against Black's king. However, since White's third move carries no immediate threat, Black can respond in a wide variety of ways.

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