Understanding chess notations - A complete biginner's guide

Chess notations are way to describe moves as natations. All books uses chess notations to explain a chess game or how chess should be played. 

A move is chess is annotated using something known as SAN or Standard Algebraic notation.  eg: If a pawn is moved from e2 square to e4 square we can annotate it as Pe4 or e4. this e4 or Pe4 is a SAN

We use “!” to denote a move as the best move in given condition

Below are symbols for classification of a move in chess:

• ! → used for the Best move
• !! → used for the brilliant move which is very difficult to find
• ?! → used for dubious move, It means the player had something better to play but this move isn't incorrect or a mistake in the given position
• ? → used to denote a mistake. The mistake in chess means the opponent now has a chance to improve his/her position or to gain advantage in the given position.
• ?? → Used to denote blunder. The blunder in chess means that the move allows opponent to either win a piece, or the game itself, or has the chance to gain winning advantage in the given position.