Why are basketball guards called "guards"? Why forwards, "forwards"?

I think "guard" and "forward" were named after defensive positions, early on. Guards were closest to the basket & so guarded the basket. Forwards were, well, players further forward on defense. On offense, the pattern holds, but in reverse: forwards are closer to the basket, while guards are further out.

1. point guard: usually the fastest player on the team, organizes the team's offense by controlling the ball and making sure that it gets to the right player at the right time. This player is typically the best dribbler and passer on the team. (ex. Jason Kidd, Chris Paul, Steve Nash)

2. shooting guard: creates a high volume of shots on offense; also called the two guard, is typically a team's best outside shooter on the team. This player flanks the point guard and moves around the court to try to create some space to take a shot that is uncontested by the opposition. guards the opponent's best perimeter player on defense (ex. Kobe Bryant, Manu Ginobli, Ray Allen)

3. small forward: often primarily responsible for scoring points via cuts to the basket and dribble penetration; The small forward is typically a better outside shooter than a power forward and is usually smaller than a power forward. on defense seeks rebounds and steals, but sometimes plays more actively (ex.LeBron James, Bruce Bowen, Carmelo Anthony)

4. power forward: plays offensively often with his back to the basket; The power forward is usually near the basket and moves from one side of the basket to the other to try to get free from the opposition player that is guarding him. Power forwards also are skilled rebounders. on defense, plays under the basket (in a zone defense) or against the opposing power forward (in man-to-man defense) (ex. Dirk Nowitzki, Drew Gooden, David West)

5. center: uses size to score (on offense), The center's role is to establish a position near the basket to allow him/herself an easy jump shot. On defense, the center attempts to block shots and grab rebounds and protect the basket closely (on defense), or to rebound. (ex. Yao Ming, Dwight Howard, Brad Miller)

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