Wikipedia: Baseball/Fielding positions

Difference (from prior minor revision) (major diff, author diff)

Changed: 6c6

* 2B: Second Base (4). The second baseman has an important defensive role to field ground balls hit toward him and, if necessary start a double play.

* 2B: Second Base (4). The second baseman has an important defensive role to field ground balls hit toward him and, if necessary start a double play. When the ball is hit to the shortstop, the second baseman may help "turn" a double play by stepping on second base, fielding the throw from SS, and throwing to first base, to retire both the batter, and the runner on first.

P: Pitcher (Position "number" 1).
C: Catcher (2)
1B: First Base (3). The first baseman's job, in addition to fielding balls hit in his direction, is primarily to catch throws from the other infielders (2B, 3B and SS) in order to retire the batter and prevent him from getting on base. When a runner is on first base, the first baseman will tend to stand on or near the bag, holding the runner close to avoid being "picked off" by the pitcher.
2B: Second Base (4). The second baseman has an important defensive role to field ground balls hit toward him and, if necessary start a double play. When the ball is hit to the shortstop, the second baseman may help "turn" a double play by stepping on second base, fielding the throw from SS, and throwing to first base, to retire both the batter, and the runner on first.
3B: Third Base (5)
SS: Short Stop (6). The shortstop, like the second baseman must field ground balls and start or turn double plays. In addition, they need a stronger arm as the throw to first base is further from the shortstop side.
LF: Left Field (7), CF: Center Field(8). RF: Right Field (9).

poor diagram by me, using XFig. Public domain :) -- GWO