Semi-open games (Sicilian, Caro-Kann, Pirc)

Black's most combative reply. Instead of copying White in the centre, Black fights for it from the side and plays for a win with the extra central pawn. Sharp, deeply analysed, and hugely popular.

The French's sturdier cousin: Black challenges the centre with …d5 but keeps the light-squared bishop free. Reliable and hard to crack — a great choice for players who like a safe, sound game.

Black challenges the centre at once with 1…d5. After 2.exd5 Qxd5 the queen comes out early but is chased to a safe square, leaving Black with a solid, easy-to-learn structure and no long theory to memorise.

Black lets White build a big centre, then attacks it from a distance with a fianchettoed bishop and timely pawn breaks. A hypermodern, counter-punching defence that leads to sharp, unbalanced middlegames.

Black provokes White into overextending. The knight invites the centre pawns forward — 2.e5, 3.d4, 4.c4 — then sets about attacking that big pawn front from all sides. Hypermodern, provocative and sharp.

Black hands White the centre, fianchettoes on g7 and strikes back later with …c5, …d6 and …e5 or …b5. Hypermodern and flexible, it invites White to overextend and then undermines the big pawns.

White sidesteps the mountains of Open Sicilian theory, fianchettoes on g2 and plays a King's-Indian-Attack-style build-up with f4 and a kingside push. A system opening: plans over memorisation.

A direct anti-Sicilian: White plays f4, Nf3 and Bb5/Bc4 to blast open the f-file and attack Black's king. Aggressive, easy to learn, and a nightmare for the unprepared.

White sacrifices a pawn for rapid development and open c- and d-files against the Sicilian. Easy to play with clear attacking targets on c7, f7 and the half-open files — a practical club weapon.

Black fianchettoes the queen's bishop with …b6 and …Bb7, striking at e4 from the flank in hypermodern style. Flexible and offbeat, it lets Black avoid mainstream theory and play for a slow counterpunch.

Black plays the committal …e5, accepting a backward d-pawn and a hole on d5 in return for dynamic piece play and the bishop pair. Once thought dubious, now a mainline weapon at the very top.

Black fianchettoes early with …g6 and delays …d6, aiming for a quick …d5 break in one go and sidestepping some of the Dragon's sharpest attacks. Solid, flexible, and a touch less theory-heavy than its cousin.

The most celebrated Sicilian and one of the most analysed openings in chess. The modest …a6 controls b5 and keeps every option open before Black commits — the choice of world champions from Fischer to Kasparov.

Black fianchettoes the 'dragon' bishop on g7, aiming it down the long diagonal at White's queenside. Opposite-side castling leads to a legendary attacking race — White storms h-file, Black the c-file — with no quarter given.

White grabs space with 3.e5 and Black develops the light-squared bishop OUTSIDE the pawn chain with …Bf5 — the whole point of the Caro over the French. A solid, strategic battle over the advanced e5-pawn and the light squares.

A flexible, modern Sicilian where Black develops …Nc6 and …e6 and keeps the pawn structure fluid, delaying …d6 to retain the option of …d5 in one move. Solid, tricky, and hard to attack.

Black builds the famous 'small centre' with pawns on d6 and e6 — modest but immensely resilient and flexible, springing …d5 or …b5 breaks at the right moment. A strategic Sicilian favoured by Kasparov.

White answers the Sicilian with 2.c3, preparing d4 and a big centre while dodging the mountains of Open Sicilian theory. Solid and strategic, it's a favourite of players who want to steer for a comfortable, well-understood middlegame.

White pins and eyes the c6-knight with 3.Bb5, aiming to damage Black's structure with Bxc6 and play a strategic game — again sidestepping Open Sicilian theory. Extremely popular at every level for its low risk and clear ideas.

The main-line Caro-Kann: Black exchanges on e4 and develops the light-squared bishop actively to f5 before …e6. Rock-solid and strategically rich, it gives Black a sound structure and a good bishop — the hallmark of the Caro.

Black develops a knight to c6 immediately, inviting White to build a big centre that Black then undermines — pure hypermodernism in the spirit of Nimzowitsch. Offbeat and flexible, it dodges mainstream 1.e4 theory and leads to original middlegames.

A flexible, low-maintenance Sicilian: Black plays …e6 and …a6 to build a small, resilient centre and keep every piece's development open. It sidesteps the sharpest theory of the Najdorf and Sveshnikov while retaining the Sicilian's winning chances.

The 'small centre' Sicilian: Black places pawns on d6 and e6, a modest but flexible structure that supports the key …d5 and …e5 breaks and gives every piece a natural square. Rich and resilient, it was a cornerstone of Kasparov's repertoire — though White's Keres Attack (g4) keeps it sharp.

Black develops both knights naturally (…Nf6 and …Nc6) before committing the rest of the pieces — the most classical, principled Open Sicilian setup. Flexible and sound, it keeps options open between …e5, …g6 and …e6 systems and steers clear of the sharpest Najdorf theory.

The main test of the Classical Sicilian: with 6.Bg5 White pins the knight, prepares Qd2 and long castling, and heads for a kingside pawn storm. A sharp, deeply-analysed battle where White attacks the king and Black seeks queenside and central counterplay.

An aggressive anti-Caro try: 3.f3 props up e4 and prepares to build a big centre and attack, avoiding the well-trodden Advance and Classical roads. Less theoretical but genuinely dangerous — a favourite of attacking players who want to take the Caro-Kann out of its comfort zone.

A hypermodern defence: Black lets White build a big centre, fianchettoes the king's bishop, and counterattacks the centre later with …e5 or …c5. The Classical (4.Nf3) is White's solid main line — flexible, and a favourite of players who want an unbalanced game without heavy theory.

An anti-Sicilian that ducks the huge Open Sicilian theory: 3.Bb5+ checks immediately, planning to trade the bishop and reach a slightly better, easy-to-play position. Solid and low-maintenance, it's a favourite of players who want a Sicilian without memorising the Najdorf and Sveshnikov.

A rock-solid Caro line favoured by Karpov: Black plays 4…Nd7 to prepare …Ngf6 without allowing the doubled pawns that 4…Nf6 invites. Ultra-sound and flexible, it aims for a healthy structure and easy development, and remains a top-level main line.

Black recaptures on f6 with the e-pawn, accepting doubled f-pawns in exchange for a half-open e-file, quick development and the bishop pair's freedom. A resilient, slightly offbeat Caro that trades a structural concession for active piece play — solid and hard to break down.

A fighting, unbalanced Caro: Black recaptures on f6 with the g-pawn, accepting a shattered kingside in return for the open g-file, dynamic piece play and attacking chances. Much sharper than the usual solid Caro lines — a choice for players who want to play for a win with Black.

A natural, flexible Open Sicilian where both sides develop all four knights before committing pawns. Black keeps options between …Bb4, …d6 and …d5 breaks, aiming for quick, harmonious development — a sound and practical way into the Sicilian without the sharpest theory.

A provocative Sicilian sideline: 2…Nf6 attacks e4 at once, inviting 3.e5 and a hypermodern battle over White's advanced pawn. Offbeat and sharp, it takes the game away from the heavily-analysed Open Sicilians into original, concrete play.

White trades in the centre immediately, leading to a symmetrical-looking pawn structure where the fight is over the isolated or hanging d-pawn and piece activity rather than a wild attack. A calm, strategic way to meet the Caro-Kann without wading into its sharper main lines.

White's most ambitious answer to the Pirc: a big pawn centre backed by f4, aiming to overrun Black before the fianchettoed bishop and flexible structure pay off. Sharp and demanding for both sides — White must convert the space advantage quickly, or the extended centre becomes a target.