The putter is used for the game on the green. In contrast to all other clubs, it is not the flight of the ball that is aimed at, but the purposeful roll into the hole. With the putter very different designs are possible because the club is swinging so slowly that there are fewer physical limitations than the other clubs.
Common to all putters is the vertical or nearly vertical face (80 ° to 90 °), because only so a uniform roll behavior of the ball can be achieved. The putter is especially important as it is used more often than any other racket (the par standard assumes two putts per fairway).