ECO Codes
The ECO Codes is a clasification system for the chess openings moves. Below is a list of chess openings organized by the Encyclopaedia of Chess Openings (ECO) code. The openings are divided in five volumes labeled from "A" through "E".
| ECO | Moves | Opening | ||
| C71 | 1. e4 e5 2. Nf3 Nc6 3. Bb5 a6 4. Ba4 d6 | Ruy Lopez, modern Steinitz defence | ||
| C72 | 1. e4 e5 2. Nf3 Nc6 3. Bb5 a6 4. Ba4 d6 5. O-O | Ruy Lopez, modern Steinitz defence, 5.O-O | ||
| C73 | 1. e4 e5 2. Nf3 Nc6 3. Bb5 a6 4. Ba4 d6 5. Bxc6+ bxc6 6. d4 | Ruy Lopez, modern Steinitz defence, Richter variation | ||
| C74 | 1. e4 e5 2. Nf3 Nc6 3. Bb5 a6 4. Ba4 d6 5. c3 | Ruy Lopez, modern Steinitz defence | ||
| C75 | 1. e4 e5 2. Nf3 Nc6 3. Bb5 a6 4. Ba4 d6 5. c3 Bd7 | Ruy Lopez, modern Steinitz defence | ||
| C76 | 1. e4 e5 2. Nf3 Nc6 3. Bb5 a6 4. Ba4 d6 5. c3 Bd7 6. d4 g6 | Ruy Lopez, modern Steinitz defence, fianchetto (Bronstein) variation |