# Chess Opening Theory/1. e4
## 1. e4 · King's Pawn Opening

The move 1. e4, the King's Pawn Opening, is the most popular first move at all levels of the game and was the favorite opening move of world champion Bobby Fischer, who called it 'best by test.' White's assertive opening move opens lines for the queen and the king's bishop (a good thing to do).
1. e4 also fights for control of d5 and f5, which might or might not be relevant later, because Black if they wanted to could just take those squares away again by playing 1...e6. If White wants to develop some pieces, the most important square they control by playing 1. e4 is, in fact, the e4 square itself. As long as there's a white pawn on e4, there can't be a black pawn on e4, which means White's g1-knight can be developed to f3 without fear of getting kicked away by a pawn and losing a tempo.
Just as White indirectly claims the f3 square by playing e4, Black has to bear in mind that f6 will not be a safe square for Black's g8-knight if White can simply advance their e4-pawn to e5. The simplest way for Black to fix this problem would be to copy White and play 1...e5 in response. White may also be dreaming of playing d4 next move, creating a strong 'classical' center, and 1...e5 by Black interferes with that plan.
Openings with 1. e4 are traditionally considered more sharp and attacking than those with 1. d4, but this is an extreme generalization, and both players will have many more opportunities to influence the type of position that appears. 1. e4 positions are in general more forcing than 1. d4 positions, meaning that the number of good moves in any position is lower because your opponent is threatening to do something horrid to you, which can make them easier for beginners to understand.

### Black's responses

Games in which Black responds with 1...e5 are called Open Games, whereas games with Black responding by any other move are known as Semi-Open Games (or Asymmetrical King's Pawn Games). It's useful to think of black's responses to 1. e4 as motivated by one of the following counterplans:
* Establish a pawn on e5, securing a share of the centre for Black (1...e5).
* Establish a pawn on d5, securing a share of the centre for Black (1...c6 or 1...e6).
* Attack White's e-pawn immediately (1...d5 or 1...Nf6).
* Leave White's e-pawn alone but prevent white from achieving the classical centre with e4 and d4 (1...e5 or 1...c5).
* Ignore what White is doing, allow White to build the classical centre and deal with it later (1...d6, 1...g6, 1...Nc6, 1...b6, or 1...a6).

#### Plan 1

| | a | b | c | d | e | f | g | h | |
| 8 | | | | | | | | | 8 |
| 7 | | | | | | | | | 7 |
| 6 | | | | | | | | | 6 |
| 5 | | | | | | | | | 5 |
| 4 | | | | | | | | | 4 |
| 3 | | | | | | | | | 3 |
| 2 | | | | | | | | | 2 |
| 1 | | | | | | | | | 1 |
| | a | b | c | d | e | f | g | h | |
Plan 1 (pawn on e5, share centre) can be carried out very simply with 1...e5. Black sees what White has and wants the same thing. However, White's argument is that moving first in a symmetrical position is eventually going to favour the player moving first.

#### Plan 2

Plan 2 (pawn on d5, share centre) is the motivation behind 1...c6, the Caro-Kann Defence, and 1...e6, the French Defence. If Black tries to put a pawn on d5 immediately, White will capture it, so in order to maintain a pawn on d5 Black needs to be able to recapture with a pawn from either c6 or e6.

#### Plan 3

Plan 3 (attack White's e-pawn) leads to 1...d5, the Scandinavian Defence, and 1...Nf6, the Alekhine Defence.

#### Plan 4

Plan 4 (prevent White's broad center with both e4 & d4) is a pleasant side effect of 1...e5 (mentioned above for Plan 1).
But, with 1...c5, the Sicilian Defence, Black can prevent White's d4 advance and also create an asymmetrical position of attack and counter-attack. The Sicilian and 1...e5 are the most popular replies to 1. e4 among top players.

#### Plan 5

There are multiple ways of carrying out Plan 5 (ignore White's centre, deal with it later).
* 1...g6, the Modern Defence, signals Black's intention to put a bishop on g7 controlling a swathe of the centre, before deciding on further action.
* 1...d6 is the Pirc Defence, a hypermodern response to White's 1. e4.
In the Pirc Defence, the move 1...d6 prepares the move 2...Nf6. In Alekhine Defence (mentioned above for Plan 3), 1...Nf6 can be met by 2. e5 kicking the knight back. But, in the Pirc, after 1...d6 2. d4 Nf6, the move 3. e5 doesn't work because of 3...dxe5 4. dxe5 Qxd1+ 5. Kxd1 Ng4! forking the pawns on e5 and f2.
So instead, White's usual move to defend the e-pawn is 3. Nc3. Now, White's d-pawn is vulnerable to the advances 3...c5 or 3...e5 because neither White's e-pawn nor c-pawn can defend it.
Plan 5 also covers a number of fringe options.
* 1...Nc6, the Nimzowitsch Defence. Black is able to react to 2. d4 with a thrust of either the d-pawn or e-pawn.
* 1...b6 is a similar idea to 1...g6 but doesn't have the benefit of preparing kingside castling.
* 1...a6 is mostly famous for having been played by Tony Miles against then World Champion Anatoly Karpov, and having thus acquired the name St. George Defence. Often Black will follow up with 2...b5, expanding on the queenside.

### Rare Responses

Other rare responses include:
* 1...f5?, the Fred Defence/Duras Gambit. This is not too good of an idea. Black gets a lead in development but little compensation for the sacrificed pawn after 2. exf5 Nf6. This can lead to another variation of the Fool's Mate after 2. exf5 g5?? 3. Qh5#
* 1...f6?, the Barnes Defence. A rare move that is not a good idea, as it removes the f6 square for the knight and weakens the kingside. Even so, Thomas Wilson Barnes (after whom it is named) beat Paul Morphy, one of the most influential grandmasters in the 19th century, with this opening. Its only benefit is that it gets out of theory.
* 1...g5?, the Borg Defence (opposite of Grob) is another option Black has, however it is a bad one because it does weaken the kingside severely. The g5-pawn can serve as a hook for White (h4) later on. This also can lead to a Fool's Mate for Black.
* 1...a5?!, the Ware Defence is equally weak as 1...h5. It just wastes a tempo.
* 1...h5?!, the Pickering Defence simply wastes a tempo and weakens Black's position.
* 1...h6?!, the Carr Defence, is another time-wasting move, but it usually transposes into the Borg Defence anyways after 2. d4 g5.
* 1...Na6?! develops the b8-knight to an inferior square.
* 1...Nh6?! develops the g8-knight to an inferior square.
* 1...b5? simply loses a pawn to 2. Bxb5.

## Statistics
### Approximate chances

    White win 39%, Draw 29%, Black win 32%.

### Estimated next move popularity

    c5 39%, e5 26%, e6 12%, c6 8%, d5 4%, d6 4%, g6 3%, Nf6 2%, Nc6 1%, b6 1%, other moves less than 0.5%.
| move | average | 365Chess.com (big) | Chess Tempo (all) | chessgames.com | Lichess (masters) | Lichess (database) |
| 1...c5 | 39.1% | 41.4 | 43.0 | 41.2 | 46.3 | 23.4 |
| 1...e5 | 25.9 | 24.0 | 22.2 | 28.6 | 22.7 | 31.8 |
| 1...e6 | 12.4 | 13.1 | 12.9 | 12.0 | 12.1 | 11.8 |
| 1...c6 | 7.8 | 7.4 | 8.2 | 7.4 | 7.8 | 8.3 |
| 1...d5 | 4.1 | 3.5 | 3.2 | 2.0 | 2.0 | 9.9 |
| 1...d6 | 4.0 | 4.3 | 4.3 | 3.5 | 3.6 | 4.3 |
| 1...g6 | 3.1 | 3.0 | 3.0 | 2.7 | 2.9 | 3.9 |
| 1...Nf6 | 2.1 | 2.3 | 2.1 | 1.8 | 1.8 | 2.5 |
| 1...Nc6 | 0.8 | 0.7 | 0.7 | 0.5 | 0.5 | 1.4 |
| 1...b6 | 0.6 | 0.3 | 0.3 | 0.2 | 0.2 | 2.0 |
| 1...a6 | 0.1 | 0.1 | 0.1 | 0.1 | 0.0 | 0.3 |
| 1...f5 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.2 |
| everything else | 0.1 | 0.0 | 0.0 | 0.0 | 0.0 | 0.3 |

## Theory table

1. e4
| | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | Evaluation |
| Sicilian Defence | ... c5 | Nf3 d6 | d4 cxd4 | Nxd4 Nf6 | Nc3 a6 | Be3 e5 | Nb3 Be6 | f3 Be7 | Qd2 O-O | +/= |
| Ruy Lopez | ... e5 | Nf3 Nc6 | Bb5 a6 | Ba4 Nf6 | O-O Be7 | Re1 b5 | Bb3 d6 | c3 Na5 | Bc2 c5 | +/- |
| French Defence | ... e6 | d4 d5 | Nc3 Nf6 | Bg5 Be7 | e5 Nfd7 | Bxe7 Qxe7 | f4 O-O | Nf3 c5 | Qd2 Nc6 | +/= |
| Caro-Kann Defence | ... c6 | d4 d5 | Nc3 dxe4 | Nxe4 Bf5 | Ng3 Bg6 | h4 h6 | Nf3 Nd7 | h5 Bh7 | Bd3 Bxd3 | +/= |
| Scandinavian Defence | ... d5 | exd5 Qxd5 | Nc3 Qa5 | d4 Nf6 | Nf3 c6 | Bc4 Bf5 | Bd2 e6 | Nd5 Qd8 | Nxf6 Qxf6 | +/= |
| Pirc Defence | ... d6 | d4 Nf6 | Nc3 g6 | f4 Bg7 | Nf3 O-O | Bd3 Na6 | O-O c5 | d5 Rb8 | Qe2 Nc7 | +/- |
| Modern Defence | ... g6 | d4 Bg7 | Nc3 d6 | f4 a6 | Nf3 b5 | Bd3 Bb7 | Qe2 Nc6 | e5 Nh6 | d5 Nb4 | +/- |
| Alekhine Defence | ... Nf6 | e5 Nd5 | d4 d6 | c4 Nb6 | f4 dxe5 | fxe5 c5 | d5 e6 | Nc3 exd5 | cxd5 Qh4+ | +- |
| Nimzowitsch Defence | ... Nc6 | d4 d5 | e5 Bf5 | Nf3 e6 | Bb5 a6 | Bxc6+ bxc6 | O-O c5 | c3 cxd4 | cxd4 h6 | +- |
| Owen Defence | ... b6 | d4 Bb7 | Bd3 e6 | Nf3 c5 | c3 Nf6 | Qe2 Be7 | O-O Nc6 | e5 Nd5 | dxc5 bxc5 | +/- |
| St. George Defence | ... a6 | d4 b5 | Nf3 Bb7 | Bd3 Nf6 | Qe2 e6 | O-O c5 | c3 d5 | e5 Nfd7 | dxc5 Nxc5 | +/- |
| Duras Gambit | ... f5 | exf5 Nf6 | d4 d5 | Bd3 c5 | c3 c4 | Bc2 e6 | Qe2 Bd6 | fxe6 Qe7 | Nf3 Bxe6 | +- |
| Barnes Defence | ... f6 | d4 e6 | Bd3 Ne7 | Nf3 c5 | d5 d6 | O-O Ng6 | Nc3 e5 | Re1 Be7 | Ne2 O-O | +- |
| Borg Defence | ... g5 | d4 Bg7 | Bxg5 c5 | c3 Qb6 | Nf3 cxd4 | cxd4 Nc6 | Nc3!? Nxd4 | Nd5! Qxb2 | Rc1 Nxf3+ | +- |
| Ware Defence | ... a5 | d4 e6 | Nc3 d5 | Bd3 Nc6 | Nf3 Nb4 | Be2 dxe4 | Nxe4 h6 | O-O Nf6 | Nxf6+ Qxf6 | +- |
| Pickering Defence | ... h5 | d4 e6 | Nf3 d5 | exd5 exd5 | Bd3 Bd6 | O-O Kf8 | Re1 Nc6 | h3 Nb4 | Bf1 Bf5 | +- |
| Carr Defence | ... h6 | d4 e6 | Bd3 d5 | Nc3 c5 | dxc5 Bxc5 | exd5 exd5 | Bb5+ Nd7 | Qxd5 Qe7+ | Qe4 a6 | +/- |
| O'Neill Gambit | ... b5 | Bxb5 Bb7 | Nc3 Nf6 | Qe2 e6 | Nf3 a6 | Ba4 c5 | O-O Nc6 | Bxc6 Bxc6 | Ne5 Bb7 | +- |

## All possible Black's moves

| Quick Navigation | Na6 a6 a5 | b6 b5 | Nc6 c6 c5 | d6 d5 | e6 e5 | Nf6 f6 f5 | g6 g5 | Nh6 h6 h5 |

## References

* Kasparov, Garry, & Keene, Raymond 1989 Batsford chess openings 2. ISBN 0-8050-3409-9.
* Nunn's Chess Openings. 1999. John Nunn (Editor), Graham Burgess, John Emms, Joe Gallagher. ISBN 1-8574-4221-0.
* Modern Chess Openings: MCO-14. 1999. Nick de Firmian, Walter Korn. ISBN 0-8129-3084-3.

## External links

* 365Chess: 1. e4
For explanation of theory tables, see theory table and for notation, see algebraic notation.
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