Caro–Kann Defence


The Caro–Kann Defence is a chess opening characterised by the moves:
The Caro–Kann is a common defence against the King's Pawn Opening and is classified as a "Semi-Open Game" like the Sicilian Defence and French Defence, although it is thought to be more solid and less dynamic than either of those openings. It often leads to good endgames for Black, who has the better pawn structure.

History

The opening is named after the English player Horatio Caro and the Austrian player Marcus Kann who analysed it in 1886. Kann scored an impressive 24-move victory with the Caro–Kann Defence against German-British chess champion Jacques Mieses at the 4th German Chess Congress in Hamburg in May 1885:

Main line: 2.d4 d5

After 2. the most common moves are 3., 3., 3., and 3..

3.Nc3 and 3.Nd2

3.Nc3 and 3.Nd2 usually transpose into each other after 3...dxe4 4.Nxe4. Since the 1970s, 3.Nd2 has increased in popularity to avoid the Gurgenidze Variation ; however, some players choose to allow it.

Classical Variation: 3...dxe4 4.Nxe4 Bf5

The most common way of handling the Caro–Kann, the Classical Variation, is defined by the moves: 1.e4 c6 2.d4 d5 3.Nc3 dxe4 4.Nxe4 Bf5. This was long considered to represent best play for both sides in the Caro–Kann. White usually continues: 5.Ng3 Bg6 6.h4 h6 7.Nf3 Nd7 8.h5 Bh7 9.Bd3 Bxd3 10.Qxd3. Although White's pawn on h5 looks ready to attack, it can prove to be a weakness in an endgame.
Much of the Caro–Kann's reputation as a defence stems from this variation. Black makes very few compromises in pawn structure and plays a timely...c6–c5 to contest the d4-square. Variations with Black castling gave the Caro–Kann its reputation of being solid but somewhat boring. More popular recently are variations with Black castling and even leaving his king in the. These variations can be and dynamic.
Here is a illustrating White's attacking chances when the players castle on opposite sides in the Classical Variation:

Modern Variation: 3...dxe4 4.Nxe4 Nd7

Another solid line, this variation is characterised by the moves: 1.e4 c6 2.d4 d5 3.Nc3 dxe4 4.Nxe4 Nd7. At one time named after the first world champion Wilhelm Steinitz, nowadays the variation is variously referred to as the Smyslov Variation after the seventh world champion Vasily Smyslov who played a number of notable games with it, the Karpov Variation, after the twelfth world champion Anatoly Karpov, in whose repertoire it appeared quite often, or, most commonly, the Modern Variation. The short-term goal of 4...Nd7 is to ease by the early exchange of a pair of knights without compromising the structural integrity of Black's position. Play is similar to the Classical Variation except that Black has more freedom by delaying the development of his bishop, and is not forced to play it to the g6-square. However, this freedom comes at a cost as White enjoys added freedom in taking up space in the centre, and often plays the aggressive 5.Ng5 where Black's development is brought into question as well as the positional weakness of the f7-square. The famous last game of the Deep Blue versus Garry Kasparov rematch where Kasparov committed a known blunder and lost was played in this very line.
Specialist knowledge is a must to play this opening. Otherwise Black could fall prey to early attacks such as the quick mating for White, 5.Qe2 followed by 6.Nd6#.

3...dxe4 4.Nxe4 Nf6 5.Nxf6+

The Bronstein–Larsen Variation and Korchnoi Variation both begin with the moves: 1.e4 c6 2.d4 d5 3.Nc3 dxe4 4.Nxe4 Nf6!? 5.Nxf6+.
Bronstein–Larsen Variation: 5...gxf6
Black has voluntarily opted for an inferior pawn structure and a practical necessity of castling queenside, while gaining dynamic compensation in the form of the open g-file for the rook and unusually active play for the Caro–Kann. It is generally considered somewhat unsound, though world championship challenger David Bronstein and former world championship candidate Bent Larsen employed it with some success.
Korchnoi Variation: 5...exf6
played 5...exf6 many times, and this line has also been employed by Ulf Andersson. Black's 5...exf6 is regarded as sounder than 5...gxf6!? of the Bronstein–Larsen Variation and offers Black rapid development, though also ceding White the superior pawn structure and long-term prospects.

Gurgenidze Variation: 3.Nc3 g6

The Gurgenidze Variation is 1.e4 c6 2.d4 d5 3.Nc3 g6. Black prepares to fianchetto the bishop on g7, creating pressure against White's d4-pawn. After 4.Nf3 Bg7 White usually plays 5.h3 to prevent the...Bg4 pin. This variation, originated by Bukhuti Gurgenidze, led to a rise in the popularity of 3.Nd2 during the 1970s. After 3.Nd2, 3...g6 is met by 4.c3, when the fianchettoed bishop has little to do. 3.Nd2 will usually transpose into the Classical Variation after 3...dxe4 4.Nxe4.

Advance Variation: 3.e5

The 3...Bf5 variation that follows with 1.e4 c6 2.d4 d5 3.e5 Bf5 has gained popularity after having previously been widely regarded as inferior for many years, owing chiefly to the strategic demolition that Aron Nimzowitsch suffered at the hands of José Capablanca in one of their games at the New York 1927 tournament.
The Advance Variation has since been revitalized by aggressive lines such as the Bayonet Attack, a popular line in the 1980s and later favoured by Latvian grandmaster Alexei Shirov, or the less ambitious variation 4.Nf3 e6 5.Be2 c5 6.Be3, popularised by English grandmaster Nigel Short and often seen in the 1990s. Another less popular but aggressive line is the Tal variation, popularised by grandmaster Mikhail Tal.
The 3...c5 variation that follows with 1.e4 c6 2.d4 d5 3.e5 c5!? is an important alternative and avoids the weight of theory associated with 3...Bf5. It was used by Mikhail Botvinnik in his 1961 match versus Mikhail Tal. The line was christened the "Arkell/Khenkin Variation" in the leading chess magazine New in Chess yearbook 42 in recognition of the work these two grandmasters did and the success they were having with the variation. In comparison to the French Defence, Black lacks the tempo normally spent on...e6; however, White can only exploit this by the weakening of his own central with 4. dxc5 when Black has good chances of regaining the pawn.

Exchange Variation: 3.exd5 cxd5

The Exchange Variation is 1.e4 c6 2.d4 d5 3.exd5 cxd5.

Main line: 4.Bd3

The Exchange Variation begins with 4.Bd3 4...Nc6 5.c3 Nf6 6.Bf4 Bg4 7.Qb3. This line is considered to offer equal chances, and was tried by Bobby Fischer. Some of the strategic ideas are analogous to the Queen's Gambit Declined, Exchange Variation, with colours reversed.

Panov–Botvinnik Attack: 4.c4

The Panov–Botvinnik Attack begins with the move 4.c4. It is named after Vasily Panov and the world champion Mikhail Botvinnik. This system often leads to typical positions, with White obtaining rapid development, a grip on e5, and kingside attacking chances to compensate for the long-term structural weakness of the isolated d4-pawn. The major variation in this line is 4...Nf6 5.Nc3 e6 6.Nf3, when Black's main alternatives are 6...Bb4 and 6...Be7, once the most common line. 6...Nc6?! is inferior as it is favourably met by 7.c5!, after which White plans on seizing the e5-square by advancing the b-pawn to b5, or by exchanging the black knight on c6 after Bb5.

Tartakower or Fantasy Variation: 3.f3

The Tartakower or Fantasy Variation, 1.e4 c6 2.d4 d5 3.f3, somewhat resembles the Blackmar–Diemer Gambit. 3...e6 is probably the most solid response, preparing to exploit the dark squares via...c5, though 3....g6 has been tried by Yasser Seirawan. GM Lars Schandorff and GM Sam Shankland both prefer 3...dxe4 4.fxe4 e5 5.Nf3 Bg4 6.Bc4 Nd7 7.0-0 Ngf6 8.c3 Bd6 with play being sharp and double-edged, though recent theory suggest that 7.c3! is more critical, giving a small objective advantage for White. Interesting, though probably insufficient is 3...e5. This so-called 'Twisted Fantasy Variation' aims to exploit White's weaknesses on the a7–g1 diagonal, an idea similar to 3...Qb6, a variation championed by Baadur Jobava. Related to the Fantasy Variation are the gambits 1.e4 c6 2.d4 d5 3.Nc3 dxe4 4.f3, originated by Sir Stuart Milner-Barry, and 1.e4 c6 2.d4 d5 3.Nc3 dxe4 4.Bc4 Nf6 5.f3 .

Two Knights Variation: 2.Nc3 d5 3.Nf3 (or 2.Nf3 d5 3.Nc3)

The Two Knights Variation 1.e4 c6 2.Nc3 d5 3.Nf3 was played by Bobby Fischer in his youth, but has since declined in popularity. White's intention is to benefit from rapid development as well as to retain options regarding the d-pawn. Black's logical and probably best reply is 3...Bg4. After 4.h3 Bxf3 5.Qxf3, the positional continuation, Black has the option of 5...Nf6 or 5...e6. The Retreat Line 4...Bh5 is but Black must be careful. In Noteboom–Mindeno 1927 Black lost quickly after 5.exd5 cxd5 6.g4 Bg6 7.Ne5 a6? 8.h4 d4 9.h5! dxc3 10.hxg6 cxd2+ 11.Qxd2 Qxd2+ 12.Bxd2 and Black must lose.
This variation sets a trap: if Black plays along the lines of the Classical Variation, he gets in trouble after 3...dxe4 4.Nxe4 Bf5 5.Ng3 Bg6?! 6.h4 h6 7.Ne5 Bh7 8.Qh5! g6 9.Bc4! e6 10.Qe2 with a huge advantage for White. Now 10...Qe7! is best. Instead, Lasker–Radsheer, 1908 and Alekhine–Bruce, 1938 ended quickly after, respectively, 10...Bg7?? 11.Nxf7! and 10...Nf6?? 11.Nxf7!
After the moves 1.e4 c6 2.Nc3 d5 3.Qf3!?, White's position is sound according to Graham Burgess.

Other lines

2.c4, the Accelerated Panov Attack, is an effective move for White. Black will probably play 2...d5. This can transpose to the Panov–Botvinnik or Caro–Kann. Alternatively, Black may play 2...e5, the Open Variation. The 2.c4 line can also arise by transposition from the English Opening: 1.c4 c6 2.e4.
The Hillbilly Attack, 1.e4 c6 2.Bc4?!, is most often played by weaker players unfamiliar with the Caro–Kann Defence. If 2...d5 3. exd5 cxd5, Black has simply gained a tempo on the bishop. Nevertheless, GM Simon Williams has experimented with this move, following it up by gambiting the pawn with 2...d5 3.Bb3!?
Other lines are ineffective or doubtful. These include 2.d3, the Breyer Variation; 2.b3, the Euwe Attack; 2.b4, the Labahn Attack; and 2.g4, the Spike Variation.

''ECO'' codes

The Encyclopaedia of Chess Openings has ten codes for the Caro–Kann Defence, B10 through B19: