I have following this tutorial http://www.chessbin.com/post/Chess-Piece-Representation to build simple chess engine right now .
at the very first step of Chess Piece Class there are many things confuse me.
why do we need many values to evaluate a chess piece for example :
pieceValue , pieceActionValue, AttackingValue, DefendingValue.
and is there any standard numerical values for evaluating chess pieces ?