Many kinds of chess notation exist, from forsythe (a notation that computers understand) to different notations for various languages. One kind of notation, however, is universally understood: algebraic, which uses a single letter and number to name each square and a letter for each chess piece. This notation system replaced the older English descriptive notation — which used an abbreviated form of a verbal description of the moves — because chess is for all people, not just Englishspeaking people.
The numbering and lettering of the chess board is oriented to the position of the player who will use the white pieces and looks like this:
As with each square for a chessboard, each chess piece also needs to be referred to by some notation, as indicated in the following table:
Piece  Notation 

King  K 
Queen  Q 
Bishop  B 
Knight  N (because K is already taken) 
Rook  R 
Pawn  [No notation] 
The letters must be capitalized to indicate a piece; otherwise, they indicate a square. The pawn doesn't get its own designation. If a move indicates only a square, you can assume that the move involves a pawn.
See how algebraic notation works in practice by examining one of the most common openings, the Ruy Lopez, or Spanish, game. Each move is numbered and includes one move by white and one move by black. The opening moves of the Ruy Lopez are written as follows:
e4 e5

Nf3 Nc6

Bb5