Chess Opening Theory/1. e4/1...e5/2. Nf3/2...Nc6

Normal variation 3. Bb5 · Ruy Lopez 3. Bc4 · Italian Game 3. d4 · Scotch Game 3. Nc3 · Three Knights Opening 3. c3 · Ponziani Opening King's knight opening 2...Nc6 · Normal variation 2...Nc6 is the natural and most common move, combining defence of the pawn with control of the d4 square. Black avoids committing another pawn for now. This is the most common position after two moves in chess. White has several choices for how to reply, which lead to very different games. Develop a piece White usually decides to develop the bishop next. While the usual advice is to "develop knights before bishops", by holding off on Nc3, White retains the option of playing c3 and d4 to take over the centre with pawns. 3. Bb5, known as the Spanish or Ruy López, is the most popular66% of games in the Lichess Master's database. and theoretical continuation. By pressuring Black's knight, White is indirectly threatening e5 which the knight defends. This usually leads to tough, positional games. The main lines are 3...a6 and 3...Nf6, though many other moves have been tried. 3. Bc4, the Italian game, develops the bishop to target Black's vulnerable f7 pawn instead. This is the second most common move, though more common in amateur games18% of games in the Lichess Master's database, 42% in the Lichess database.. Most commonly Black plays 3...Bc5, the Giuoco piano, or 3...Nf6, the Two knights defence. 3. Nc3, the three knights opening, is reached if White decides to develop their knight next after all. This is a quieter (read: drawish) continuation. Black usually plays 3...Nf6, reaching the four knights. 1. e4 e5 2. Nf3 Nc6 3. Bb5 Spanish game 1. e4 e5 2. Nf3 Nc6 3. Bc4 Italian game 1. e4 e5 2. Nf3 Nc6 3. Nc3 Three knights game Contest the centre White can prioritise contesting the centre with pawns. 3. d4, the Scotch opening, busts open the centre straight away. This is the third most common continuation. After Black captures 3...exd4, White can recapture the pawn or gambit it for development. 3. c3, the Ponziani opening, prepares d4 with the c-pawn. White would like to not just to put a pawn on d4 but keep one there. This is an uncommon continuation. 1. e4 e5 2. Nf3 Nc6 3. d4 Scotch game 1. e4 e5 2. Nf3 Nc6 3. c3 Ponziani opening Offbeat continuations The above five replies cover almost every serious game. A few very offbeat choices make up less than one percent of games combined. The ideas include: Developing the king's bishop somewhere else: 3. Be2?!, the Tayler opening, 3. Bd3, or 3. g3 in order to play 4. Bg2, the Konstantinopolsky opening. A flank move, 3. c4, the Dresden opening, to control d5 and allow the b1 knight to develop behind the pawn. 3. d3, a timid reply that avoids contesting the centre and voluntarily cramps White's position. 1. e4 e5 2. Nf3 Nc6 3. g3 Konstantinopolsky opening 1. e4 e5 2. Nf3 Nc6 3. Be2 Tayler opening 1. e4 e5 2. Nf3 Nc6 3. c4 Dresden opening 1. e4 e5 2. Nf3 Nc6 3. d3 3. d3 Bad moves Some dubious gambits: 3. Nxe5?? is the Chicago or Irish gambit. White sacrifices a knight to take over the centre uncontested, but the cost of being a minor piece down is vastly more punishing. 3. b4?, the Pachman wing gambit, where White sacrifices the b pawn to give Black a hand in development (3...Bxb4). Even if Black is equally generous (3...Nxb4? 4. Nxe5) it's at best an even game. 1. e4 e5 2. Nf3 Nc6 3. Nxe5 Irish gambit 1. e4 e5 2. Nf3 Nc6 3. b4 Pachman wing gambit Theory table 1. e4 e5 2. Nf3 Nc6 3 4 5 Ruy Lopez Bb5a6 Ba4Nf6 O-OBe7 = Italian Game Bc4Bc5 c3Nf6 d4exd4 = Scotch Game d4exd4 Nxd4Bc5 Nb3Bb4+ = Four Knights Game Nc3Nf6 d4exd4 Nxd4Bb4 = Ponziani Opening c3d5 Bb5dxe4 Nxe5Qg5 = References See also King's Knight Opening