An Open Game (or Double King's Pawn Opening) is a chess opening that begins with the following moves:

1. e4 e5

White has moved the king's pawn two squares and Black has replied in kind. The result is an Open Game. Other responses to 1.e4 are termed Semi-Open Games or Single King's Pawn Games.

It should not be confused with the term "open game" (small o), referring to a chess position where ranks, files and diagonals are open, and tending to more tactical gameplay.

Analysis

White opens by playing 1.e4, which is the most popular opening move and has many strengths—it immediately stakes a claim in the center, and frees two pieces (the queen and king's bishop) for action. The oldest openings in chess follow 1.e4. Bobby Fischer wrote that 1.e4 was "Best by test." On the negative side, 1.e4 places a pawn on an undefended square and weakens the squares d4 and f4; the Hungarian master Gyula Breyer melodramatically declared that "After 1.e4, White's game is in its last throes." If Black keeps the symmetry by replying 1...e5, the result is an Open Game (Hooper & Whyld 1992) (Watson 2006:87–90).

Defenses

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 Ruy Lopez: 3.Bb5

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 Philidor Defense: 2...d6

The most popular second move for White is 2.Nf3, attacking Black's king pawn, preparing to castle kingside, and preparing for d2–d4. Black's most common reply is 2...Nc6, which usually leads to the Ruy Lopez (3.Bb5), Italian Game (3.Bc4), or Scotch Game (3.d4), though 3.Nc3 Nf6 (the Four Knights Game), often played in the late 19th to early 20th century, or, less commonly, 3....g6 or ...Bb4, (the Three Knights Game), are other possibilities. If Black instead maintains symmetry and counterattacks White's center with 2...Nf6 then the Petrov's Defense will usually result, though White can avoid the extensive theory of the Petrov by playing 3.Nc3 if he wishes.

The Philidor Defence, (2...d6), largely fell out of use after World War I, as Black players sought positions offering more counterchances than the solid, though passive game which generally arises from this opening.

The Damiano Defense (2...f6) may be met by either 3.Nxe5 or 3.Bc4, with advantage; the Elephant Gambit (2...d5) and the Latvian Gambit (2...f5) are considered very risky for Black, with the latter usually seen only in correspondence play.

	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

King's Gambit: 2.f4

The most popular alternatives to 2.Nf3 are 2.f4 (the King's Gambit), 2.Nc3 (the Vienna Game), and 2.Bc4 (the Bishop's Opening). These three openings have some similarities; some of the quieter lines in the Vienna and Bishop's Opening can transpose to positional variations of the King's Gambit Declined, when White plays f2–f4 before playing Nf3. The King's Gambit was popular in the nineteenth century with grandmaster and amateur alike. White offers a pawn for speedy development, as well as to attack Black's central outpost. The Vienna Game also frequently features attacks on the Black center by means of f2–f4.

In the Center Game (2.d4), White immediately opens the center, though if the pawn is to be recovered after 2...exd4, White must prematurely develop his queen. An alternative is to sacrifice one or two pawns by offering the Danish Gambit (3.c3). The early development of the queen in the Danvers Opening (2.Qh5) or the Napoleon Opening (2.Qf3) looks amateurish, though the Danvers Opening (also called the Wayward Queen Attack) has been played in a grandmaster tournament by Hikaru Nakamura.

The Portuguese Opening (2.Bb5), Alapin's Opening (2.Ne2), Konstantinopolsky Opening (2.Nf3 Nc6 3.g3), and Inverted Hungarian Opening (2.Nf3 Nc6 3.Be2) are offbeat tries for White, though none promise any advantage in the face of correct play.

Examples of Open Games

• 1.e4 e5 2.Bb5 Portuguese Opening
• 1.e4 e5 2.c3 Lopez Opening
• 1.e4 e5 2.Nc3 Vienna Game
• 1.e4 e5 2.Bc4 Bishop's Opening
• 1.e4 e5 2.d4 exd4 3.c3 Danish Gambit
• 1.e4 e5 2.d4 exd4 3.Qxd4 Center Game
• 1.e4 e5 2.Ne2 Alapin's Opening
• 1.e4 e5 2.Nf3 Nc6 3.Bb5 Ruy Lopez
• 1.e4 e5 2.Nf3 Nc6 3.c3 Ponziani Opening
• 1.e4 e5 2.Nf3 Nc6 3.Nc3 without 3...Nf6 Three Knights Game
• 1.e4 e5 2.Nf3 Nc6 3.Nc3 Nf6 Four Knights Game
• 1.e4 e5 2.Nf3 Nc6 3.Bc4 Italian Game
• 1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 Giuoco Piano
• 1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.b4 Evans Gambit
• 1.e4 e5 2.Nf3 Nc6 3.Bc4 Be7 Hungarian Defense
• 1.e4 e5 2.Nf3 Nc6 3.Bc4 Nf6 Two Knights Defense
• 1.e4 e5 2.Nf3 Nc6 3.d4 Scotch Game
• 1.e4 e5 2.Nf3 Nc6 3.Be2 Inverted Hungarian Opening
• 1.e4 e5 2.Nf3 Nc6 3.g3 Konstantinopolsky Opening
• 1.e4 e5 2.Nf3 d5!? Elephant Gambit
• 1.e4 e5 2.Nf3 d6 Philidor Defence
• 1.e4 e5 2.Nf3 f5 Latvian Gambit
• 1.e4 e5 2.Nf3 f6 Damiano Defense
• 1.e4 e5 2.Nf3 Nf6 Petrov's Defence
• 1.e4 e5 2.Nf3 Qf6 Greco Defense
• 1.e4 e5 2.Qf3?! Napoleon Opening
• 1.e4 e5 2.f4 King's Gambit
• 1.e4 e5 2.Qh5 Danvers Opening

See also

References

• Hooper, David; Whyld, Kenneth (1992), The Oxford Companion to Chess (2nd ed.), Oxford University Press, ISBN 0-19-866164-9 
• Watson, John (2006), Mastering the Chess Openings, vol 1, Gambit, ISBN 978-1-904600-60-2 

Further reading

The Wikibook Chess Opening Theory has a page on the topic of: Open Game

• Djuric, Stefan; Komarov, Dimitri; Pantaleoni, Claudio (2008), Chess Opening Essentials, vol 1: the complete 1.e4, New In Chess, ISBN 978-90-5691-203-1 
• Flear, Glenn (2010), Starting Out: Open Games, Everyman Chess, ISBN 978-1-85744-630-2