In any chess game there is an opening, a middle game and an ending. Some games, especially for beginners, do not go through the three stages, but as your play improves it becomes necessary to learn some things about them.
American grandmaster and world champion Bobby Fischer was a versatile king pawn player represented by the move 1. e4. Fischer played the move incessantly against the very best in the world. Aggressive players are more likely to choose 1. e4 since there are more chances to lead the game into early confrontation. Fischer studied each response to e4 well, and you may say, until he passed, he was the leading expert on e4.