Middlegame
portion of a chess game between the opening and the endgame / From Wikipedia, the free encyclopedia
The middlegame is the part of a game of chess after the opening.
The middlegame begins when most of the pieces have been developed. It is where most games are won and lost. Many games will end in resignation even before an endgame takes place.[1]
The simplest way to learn the middlegame is to select an opening and learn it well (see examples in English opening and French defence).