An arrow is a shape used to point to something. Arrows look like this: -->. "Double-headed" arrows look like this: <-->.
An arrow is a projectile fired with a bow. A bow and arrow is a weapon used in medieval times and earlier. Nearly all cultures have used the bow and arrow in their past. Arrows have a sharp point at one end and usually a flight at the other end. The flight is usually made of feathers and helps the arrow go through the air straight.