Chess Opening Theory/1. c4/1...e5/2. Nc3/2...Nf6

= English Opening =

2...Nf6
This position, also reachable through the move orders 1...e5/2.Nc3 Nf6, can lead to two important variations of the English opening depending on how white chooses to develop. 3.Nf3 is the natural developing move and more often than not it leads to the English four knights variation simply because black must defend his pawn and the most practical way to do it is with 3...Nc6. After this white will usually develop his bishop to g2 and castle kingside. Black has a variety of options against this variation including the pinning of the knight on c3 with the dual idea of advancing the pawn on e5 and inflicting doubled pawns.

The other option for white is to get the bishop to g2 first and then choosing how to develop the knight, this idea is known as the Bremen system. The Bremen System has the advantage of maintaining flexibility in the development of the knight while also increasing control of the d5 square and putting extra pressure on black´s q-side. Black on the other hand might choose to counter this pressure by advancing his pawn to c6, the Keres variation, with the idea of creating a sturdy pawn formation which white must either undermine with his own pawns or fall to.

Theory table
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