White's move 2. Nf3 increased their control of the d4 square, enabling them to play d4 next move. Black cannot hope to resist White's plan any further, and should go about their own development.

2...d6 is the most popular move, controlling e5 to allow black to play Nf6 in the future, as well as letting the queen's bishop out, while also holding down the c-pawn should White go down a different path. This usually leads to the Najdorf, Dragon, Classical, or Scheveningen Sicilians.

2...e6 is an older, though still popular move freeing the king's bishop, although black sometimes follows up with d6 later on. This usually leads to the Kan, Taimanov, or 4 knights Sicilian.

2...Nc6 is the most traditional move, and still played often today. It reserves options in the centre and keeps an eye on d4, usually leading to the Sveshinkov, Accelerated Dragon or Kalashnikov Sicilians.

Black can also play 2...g6 (the Hyper-Accelerated Dragon) with ...Bg7 to follow, often transposing to the Accelerated Dragon or Dragon Sicilians, or 2...a6 (the O'Kelly Variation) which can restrain some of White's longer-term plans and provide the springboard for a b5 advance, though it neglects the centre.

There are many slightly different Sicilians with similar plans for Black, in which various combinations of these moves may turn up in almost any order.

The one significant departure from the main lines is 2...Nf6, evoking Alekhine's Defence by attacking the e-pawn to tempt it forward.

For explanation of theory tables, see theory table and for notation, see algebraic notation.

1. e4 c5 2. Nf3

• Nunn's Chess Openings. 1999. John Nunn (Editor), Graham Burgess, John Emms, Joe Gallagher. ISBN 1-8574-4221-0.

• Kasparov, Garry, & Keene, Raymond 1989 Batsford chess openings 2. ISBN 0-8050-3409-9.