Have you ever noticed that it is easy to play against some chess players and it’s is almost impossible to beat the other ones. You may say, of course some players are weaker and thus easier to play against, some players are stronger and thus harder to play against. But did you ask yourself a question why is this player considered strong while the other one is weak. Is that because he has openings encyclopedia build into his head, Nalimov’s endgames tables let him play perfect endgame or he can calculate zillions moves ahead? Not necessarily. All chess players want to become this sort of hard-to-deal with chess machines. But how can you do that? Is it necessary to memorize thousands opening lines and theoretical endgames?