The Benoni Defence can be divided into two main structures, which are very different in concept: the Modern Benoni, 1.d4 Nf6 2.c4 c5 3.d5 e6 4.Nc3 exd5 5.cxd5 d6 and the Czech (or Old) Benoni 1.d4 Nf6 2.c4 c5 3.d5 e5 which is much less...