Chess Principles

Traps

Never play a move that puts you in either of the following emotionally charged situations: Your opponent doesn’t see your trap and loses horribly. He sees your trap and counters in such a way that your position falls apart.
f7 and f2 pawns are only protected by Kings.

Rooks need open files to be effective.
With every turn you must ask yourself whether you are:
- Acquiring superior force in some part of the board.
- Gaining a lead in development.
- Improving your pawn structure.
- Gaining space.

An open position has a minimum number of pawns sitting in the center. Pieces are not blocked and can zip into the enemy.
Attack where you have most space to maneuver. In closed positions, you must also work hard to create open files for your Rooks.
Knights are often better than Bishops in closed positions.

The positioning of the pawns dictates the strategies available to both sides. For example, if one side has advanced his pawns and thus gained a space advantage, the other side’s strategy might be to trade pieces and decrease crowding in his cramped quarters. If one side’s pawn formation is full of weak pawns, the other side’s strategy might be to attack these weak men.
If your opponent has a weak pawn (a wound), focus your army on that pawn and make every effort to capture it.
In the endgame, whoever has the most pawn islands loses.
An isolated pawn is considered weak because it has no protecting pawns on either side to give it the support it often needs.
A good pawn is any pawn that exerts a cramping pressure on the opponent and is safe from attack. One type of pawn that fits this description is known as a passed pawn, because it has no enemy pawns in front or on either side. Such a pawn is free to advance unless the opponent assigns one of his pieces the passive task of setting up a roadblock in front of it.