Against 1.d4
King's Indian, Nimzo-Indian, Slav and Dutch: the four great replies.
Against 1.e4 you have many defences; against 1.d4 almost all of chess fits into four ideas. Two of them start with Nf6 (the Indians), one holds the centre with pawns (the Slav) and one goes for a wing attack (the Dutch). Do not choose by fashion: choose by the kind of position you enjoy playing.
The King's Indian. Black gives up the centre, gets armed, and explodes later.
The Nimzo-Indian. Instead of a pawn, a bishop pinning the knight.
The Slav. The solid answer: hold d5 with c6 and concede nothing.
The Dutch. A pawn on the f-file, and the game heads for the king.
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