Defenses to e4 without ...e5

An opening family defined by 1.e4 c5, where Black contests the center with a flank pawn.

A family of Sicilian lines where White advances the pawn in front of the queen early and trades it for Black's c-pawn.

An Open Sicilian variation in which Black plays ...a6 to control b5 and preserve several possible central structures.

A system against the Najdorf beginning with Be3 and often followed by f3, Qd2, and a pawn attack against Black's king.

A Najdorf branch full of concrete threats in which Black's queen captures on b2 and accepts danger in return for a pawn.

An Open Sicilian variation in which Black plays ...g6 to develop the bishop through g7 onto the long diagonal.

An aggressive system against the Dragon in which White prepares to place the king on c1 and advance pawns toward Black's king.

An attack against the Dragon defined by 6.f4, with which White prepares e5 and a rapid pawn advance toward the black king.

A Sicilian variation that prepares ...Bg7 without first playing ...d6, aiming to free the center with ...d5 in one move.

A Sicilian move order in which Black plays 2...g6 to open a path for the f8-bishop toward g7.

An Open Sicilian variation in which Black develops both knights to f6 and c6 before committing the central pawn structure.

An aggressive system against the Classical Sicilian in which Bg5 pressures the f6-knight and helps White bring pieces into play quickly.

A Sicilian system in which White moves the bishop from f1 to c4 to pressure f7 and accelerate attacking play.

A highly aggressive Sozin continuation with Bc4, Be3, and Qe2, usually aimed at placing White's king on c1 and attacking Black's king.

A Sicilian system with black pawns on d6 and e6, a compact center, and counterplay on either wing.

A direct attack against the Scheveningen beginning with 6.g4 and preparing g5 to drive away the f6-knight.

A dynamic Sicilian system where Black plays an early ...e5, gains space, and accepts a lasting weakness on d5.

A Sicilian variation in which Black plays ...e5 before developing the knight from g8.

A flexible Sicilian system with ...e6 and ...Nc6, designed to develop pieces and prepare the freeing ...d5 break.

A flexible Sicilian variation where Black plays ...e6 and ...a6 before deciding how to place the knights.

A Sicilian line in which both sides develop both knights quickly while preserving several choices for their central pawns.

A variation in which White recaptures on d4 with the queen instead of the knight and avoids many main branches.

A family of positions beginning with 2.Nc3 where White usually delays d4 and builds the position more gradually.

An aggressive anti-Sicilian plan where White plays f4 to gain space and prepare an attack on the king.

An anti-Sicilian system where White plays c3 to prepare a strong pawn center with d4.

A response to 2...Nc6 where White develops the bishop to b5 and postpones opening the center with d4.

A Sicilian system where White gives an early check with the bishop beside the king before opening the center.

A gambit against the Sicilian where White offers a pawn for rapid development and open central lines.

A gambit in which White offers 2.b4 to deflect the c5-pawn and build a broad center with d4.

A Sicilian line defined by 2...a6, a flexible move that controls b5 and prepares expansion on the queen's side.

A defense to 1.e4 where Black prepares ...d5 with ...e6 and challenges White's center from move two.

A variation where White plays 3.e5, gains space, and fixes a pawn chain that Black will try to attack.

A gambit in which White offers the d4-pawn to bring the pieces out quickly and create threats against the black king.

A line where White exchanges central pawns and leaves a symmetrical pawn arrangement.

A variation with 3.Nd2 that protects e4, leaves the c-pawn free, and avoids the typical Winawer position with a knight on c3.

A response to 3.Nd2 in which Black brings out the b8-knight with 3...Nc6 and prepares pressure against White's center.

A sharp variation with 3...Bb4, where Black pins the c3-knight and creates early structural imbalance.

A highly concrete line in which White's queen takes pawns near Black's king while Black attacks the queen and White's center.

A variation with 3...Nf6 where Black develops a knight and increases pressure on e4 without resolving the center.

A line in which Black plays 4...dxe4 to exchange the central pawn and give the pieces more freedom.

A sharp response to 4.Bg5 in which Black plays 4...Bb4 and pins the c3-knight to the king.

An attacking gambit beginning with 6.h4, in which White offers a pawn to open lines against the black king.

A variation in which White advances e5 after Nc3 and builds a pawn center that Black attacks with ...c5 and ...f6.

A solid variation where Black exchanges on e4 early, simplifies the center, and accepts less space.

A solid system in which Black exchanges the central pawn early and brings the c8-bishop out through ...Bd7 and ...Bc6.

A solid defense where Black uses a side pawn to support the advance of the pawn in front of the queen and challenge the center.

A line where White advances the pawn in front of the king again, gains territory, and forms a pawn chain.

An Advance Caro-Kann line where White plays 4.Nf3 to develop and support the e5-pawn.

An aggressive Advance line where White plays 4.h4 to disturb the f5-bishop and gain kingside space.

A line where White trades a central pawn and Black recaptures with a flank pawn, simplifying the center.

An aggressive Caro-Kann line where one of White's side pawns immediately attacks Black's central pawn.

A Caro-Kann system where White plays 2.c4 and challenges d5 before establishing a pawn on d4.

A common line where Black exchanges the pawn in front of White's king and brings out the bishop beside the queen before closing its diagonal.

A Caro-Kann variation where Black plays 4...Nd7 to prepare ...Ngf6 without necessarily damaging the pawn structure.

A Caro-Kann variation where ...gxf6 creates doubled pawns and a half-open g-file in return for attacking chances.

A Caro-Kann variation where ...exf6 creates doubled pawns, keeps the g-pawn in place, and opens the e-file.

A system where White brings out both knights early and delays advancing the pawn that starts in front of the queen.

A White system against the Caro-Kann where 3.f3 supports e4 and prepares an f-pawn recapture if Black exchanges.

A Caro-Kann system where Black plays 3...g6 and prepares the bishop on g7 to pressure White's center.

A defense where Black immediately challenges the pawn in front of White's king with the pawn in front of Black's queen.

An immediate-recapture line in which Black takes on d5 with the queen and retreats to a5 after Nc3.

A branch defined by 2...Nf6, with which Black brings out a knight and delays recovering the d5-pawn.

A gambit in which Black offers the e6-pawn to bring pieces out quickly and open the center after 2...Nf6.

A gambit with 3...Bg4 in which Black delays recovering the d5-pawn to bring out the bishop and create pressure.

A defense where a black knight attacks the pawn in front of White's king and invites the white pawns forward so they may become targets.

An Alekhine variation where White plays 4.Nf3, developing a piece and supporting the advanced e5-pawn.

An Alekhine Defense variation where White's e5-pawn captures on d6 and resolves the central tension early.

An ambitious Alekhine system where White occupies the center with pawns on e5, d4, c4, and f4.

A defense where Black allows White a broad center and attacks it later with pieces and pawn advances.

A flexible system with 4.Nf3 in which White brings out the second knight and keeps the central pawns on d4 and e4.

An aggressive line defined by 4.f4, with which White builds a large center and prepares the e5 advance.

An attacking system with Be3 and Qd2 in which White often castles long and advances pawns toward the black king.

A Pirc-family system where Black plays ...c6 to support d5, control b5, and prepare central pawn breaks.

A flexible defense where Black allows White a broad pawn center and attacks it later from a distance.

A system in which White builds a broad center with pawns on c4, d4, and e4 while Black prepares a counterattack.

An uncommon defense where Black prepares the bishop that starts beside the queen on a long diagonal against White's center.

A flexible defense where Black moves the knight beside the queen first and waits before deciding how to challenge the center.