before start of the game there is a state of Equalibrium. but as soon as few moves wre made this equilibrium disrupts and many IMBALANCES occures. Some of these THESE Imbalances r in one or other player's favour. THESE ELEMENTS r 1-FORCE..2-PAWN STRUCTURE..3-SPACE nd 4-DEVELOPMENT. Force nd Pawn Structure r of stable or long term ELEMENTS while Space nd Develoment r of unstable or short term ELEMENTS. thus advantage in FORCE or Pawn structure calls for exchanges to reach Basic winning endgame position. and advantage in Space nd/or Devlopment calls for active play means sharp aggresive moves to destroy opponents fortress.