After protection by 1.e4 e6 2.d4 d5 3.Nc3 and the renewed attack on e4 with 3...Nf6 we have reached the starting position for the Classical Variation. Since the exchange 4.exd5 is considered harmless, White continues either with 4.e5 (Steinitz Variation) or after 4.Bg5 Be7 with 5.e5 Nfd7; the result is the typical French pawn chain d4-e5 against d5-e6.
This structure may give White more space on the kingside, but his central pawns will be exposed to the attacks by ...c7-c5 and ...f7-f6. Black, on the other hand, must first accept a rather cramped position, when above all it is not easy to bring into play the Bc8, the French bishop.
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