The King's Pawn Game is any chess opening starting with the move: 1. e4 It is the most popular opening move in chess, followed by the Queen's Pawn Game. Details about the move and the game plan White opens with the most popular of the twenty possible opening moves. Although effective in winning for White (54.25%), it is not quite as successful as the four next most common openings for White: 1.d4 (55.95%), 1.Nf3 (55.8%), 1.c4 (56.3%), and 1.g3 (55.8%). Since nearly all openings beginning 1.e4 have names of their own, the term King's Pawn Game, unlike Queen's Pawn Game, is rarely used to describe the opening of the game. Advancing the king's pawn two squares is highly useful because it occupies a square, attacks the center square d5, and allows the of White's and queen. Chess grandmaster Bobby Fischer said that the King's Pawn Game is "Best by test", and proclaimed that "With 1.e4! I win." Opening categorization and continuations King's Pawn Games are further classified by whether Black responds with 1...e5 or not. Openings beginning with 1.e4 e5 are called Double King's Pawn Games (or Openings), Symmetrical King's Pawn Games, or Open Games – these terms are equivalent. Openings where Black responds to 1.e4 with a move other than 1...e5 are called Asymmetrical King's Pawn Games or Semi-Open Games. The Encyclopedia of Chess Openings (ECO) classifies all King's Pawn Games into volumes B or C: volume C if the game starts with 1.e4 e6 (the French Defence) or 1.e4 e5; volume B if Black answers 1.e4 with any other move. The rare instances where the opening does not fall into a more specific category than King's Pawn Game are included in codes B00 (includes the Nimzowitsch Defence and unusual moves after 1.e4), C20 (includes Alapin's Opening and unusual moves after 1.e4 e5), C40 (includes the Latvian Gambit and unusual moves after 1.e4 e5 2.Nf3), and C50 (includes the Hungarian Defence, the Giuoco Pianissimo, and unusual moves after 1.e4 e5 2.Nf3 Nc6 3.Bc4). The Black responses which are given one or more chapters in the ECO are given below, ranked in order of popularity according to ChessBase. Popular continuations 1... c5, the Sicilian Defence, is the most common continuation in modern practice. The Sicilian Defence allows Black to fight for the center by preparing to meet a d2–d4 advance with ...cxd4. The Sicilian is among the sharpest and most