Editing Chess opening (section)

===Indian defenses: 1.d4 Nf6===
{{Main article|Indian Defence|l1=Indian Defense}}
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The Indian systems are asymmetrical defenses to 1.d4 that employ hypermodern chess strategy. Fianchettos are common in many of these openings. As with the closed games, [[transposition (chess)|transpositions]] are important and many of the Indian defenses can be reached by several different move orders. Although Indian defenses were championed in the 1920s by players in the hypermodern school, they were not fully accepted until Soviet players showed in the late 1940s that these systems are sound for Black. Since then, Indian defenses have been the most popular Black replies to 1.d4 because they offer an unbalanced game with chances for both sides. The usual White second move is 2.c4, grabbing a larger share of the center and allowing the move Nc3, to prepare for moving the e-pawn to e4 without blocking the c-pawn. Black's most popular replies are:
* 2...e6, freeing the king's bishop and leading into the Nimzo-Indian Defense, Queen's Indian Defense, Bogo-Indian Defense, Modern Benoni, or regular lines of the [[Queen's Gambit Declined]],
* 2...g6, preparing a fianchetto of the king's bishop and entering the King's Indian Defense or Grünfeld Defense, and
* 2...c5 3.d5 e6, the Modern Benoni, with an immediate counterpunch in the center.

Advocated by [[Aron Nimzowitsch|Nimzowitsch]] as early as 1913, the [[Nimzo-Indian Defense]] was the first of the Indian systems to gain full acceptance. It remains one of the most popular and well-respected defenses to 1.d4 and White often adopts move orders designed to avoid it. Black attacks the center with pieces and is prepared to trade a bishop for a knight to weaken White's queenside with [[doubled pawns]].

The [[King's Indian Defense]] is aggressive, somewhat risky, and generally indicates that Black will not be satisfied with a draw. Although it was played occasionally as early as the late 19th century, the King's Indian was considered inferior until the 1940s, when it was taken up by [[David Bronstein|Bronstein]], [[Isaac Boleslavsky|Boleslavsky]], and [[Samuel Reshevsky|Reshevsky]]. Despite being [[Bobby Fischer|Fischer]]'s favored defense to 1.d4, its popularity faded in the mid-1970s. [[Garry Kasparov|Kasparov]]'s successes with the defense restored the King's Indian to prominence in the 1980s.

[[Ernst Grünfeld]] debuted the [[Grünfeld Defense]] in 1922. Distinguished by the move 3...d5, Grünfeld intended it as an improvement to the King's Indian which was not considered entirely satisfactory at that time. The Grünfeld has been adopted by World Champions [[Vasily Smyslov|Smyslov]], Fischer, and Kasparov.

The [[Queen's Indian Defense]] is considered solid, safe, and perhaps somewhat [[draw (chess)|drawish]]. Black often chooses the Queen's Indian when White avoids the Nimzo-Indian by playing 3.Nf3 instead of 3.Nc3. Black constructs a sound position that makes no positional concessions, although sometimes it is difficult for Black to obtain good winning chances. [[Anatoly Karpov|Karpov]] was a leading expert in this opening.

The [[Modern Benoni]] is a risky attempt by Black to unbalance the position and gain active piece play at the cost of allowing White a pawn wedge at d5 and a central majority. [[Mikhail Tal|Tal]] popularized the defense in the 1960s by winning several brilliant games with it, and Fischer occasionally adopted it, with good results, including [[World Chess Championship 1972#Game 3|a win]] in his [[World Chess Championship 1972|1972 world championship]] match against [[Boris Spassky]]. Often Black adopts a slightly different move order, playing 2...e6 before 3...c5 in order to avoid the sharpest lines for White.

The [[Benko Gambit]] is often played by strong players, and is very popular at lower levels. Black plays to open lines on the queenside where White will be subject to considerable pressure. If White accepts the gambit, Black's compensation is positional rather than tactical, and their initiative can last even after many piece exchanges and well into the [[Chess endgame|endgame]]. White often chooses instead either to decline the gambit pawn or return it.

The [[Catalan Opening]] is characterized by White forming a pawn center at d4 and c4 and fianchettoing their king's bishop. It resembles a combination of the [[Queen's Gambit]] and [[Réti Opening]]. Since the Catalan can be reached from many different move orders, (one [[Queen's Gambit Declined]]-like move sequence is 1.d4 d5 2.c4 e6 3.Nf3 Nf6 4.g3), it is sometimes called the Catalan System.

The most important Indian Defenses are listed below, but many others have been studied and played; see [[Indian Defense]] for details.
* 1.d4 Nf6 2.c4 c5 3.d5 e6 [[Modern Benoni]]
* 1.d4 Nf6 2.c4 c5 3.d5 b5 [[Benko Gambit]] (or Volga Gambit)
* 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 [[Nimzo-Indian Defense]]
* 1.d4 Nf6 2.c4 e6 3.Nf3 b6 [[Queen's Indian Defense]]
* 1.d4 Nf6 2.c4 e6 3.g3 [[Catalan Opening]]
* 1.d4 Nf6 2.c4 g6 3.Nc3 d5 [[Grünfeld Defense]]
* 1.d4 Nf6 2.c4 g6 3.Nc3 Bg7 [[King's Indian Defense]] (KID)