The point guard in basketball, a.k.a. the "1," is the player who takes care of the majority of ball handling, especially bringing the ball up the court. A nickname for the point guard is the "floor general," as he usually calls all of the plays and executes the action. He is usually an adept dribbler, passer, and penetrator, enabling him to rack up assists. The three most prolific assist men in NBA history are John Stockton, Earvin "Magic" Johnson, and Mark Jackson.
While the point guard's J is not a smooth as that players of other positions, i.e. he usually has less pure shooting ability than the shooting guard or small forward, there are many point guards who were or are excellent scorers, notably Hall of Famers Oscar Robertson and Magic Johnson, recent NBA MVP Allen Iverson, and other current stars Jason Kidd, Stephon Marbury, Gary Payton and Steve Nash. This meshes with the recent NBA trend of players fitting in at more than one position and blurring established roles.
Guards are generally towards the short end of the spectrum of basketball height, averaging 6'2" (that's not a statistical fact, just an estimation), but many great guards have been taller, including Michael Jordan (6'6", shooting guard), Kobe Bryant (6'7", SG), Vince Carter (6'6", SG), Infernal "Penny" Hardaway (6'7", SG) and Tracy McGrady (6'8", SG). Two of the shortest NBA players in history were or are point guards: 5'5" Earl Boykins and the retired Muggsy Bogues, who stands a mountainous 5'3".
Note: I know members of the female gender also play basketball, but I used the male reference words throughout the w/u because it's more coherent than switching and I mainly refer to male players.