Ruy Lopez Ajedrez", written in 1561. Although it bears his name, this particular opening was included in the Göttingen manuscript, which dates from c. 1490. However, popular use of the Ruy Lopez opening did not develop until the mid-19th century, when Carl Jaenisch, a Russian theoretician, "rediscovered" its potential. The opening remains the most commonly used amongst the open games in master play; it has been adopted by almost all players during their careers, many of whom have played it with both colours. Due to the difficulty for Black in achieving equality, a common nickname for the opening is "The Spanish Torture".
Libro de la invencion liberal y arte del juego del axedrez the second part, López introduces the word "gambit" and gives some openings that had not been previously published: the King's Gambit, some variations of the Bishop's Opening, and what is now known as the Steinitz Defense in the Ruy Lopez. The last two parts of the book are critical of the games of Damiano. After the moves 1.e4 e5 2.Nf3, Damiano thought that 2...Nc6 was Black's best move. López considered that inferior because of 3.Bb5. This opening is now known as the Ruy Lopez, although he did not invent it . Libro de la invencion liberal y arte del juego