In sailing, when two vessels approach each other with the wind coming from different sides, the vessel that has the wind on its port side (left side when facing forward) is typically considered the stand-on vessel, while the other is the give-way vessel. If vessel A has the wind on its starboard side, it must give way to vessel B, which has the wind on its port side. This rule helps maintain safety at sea by establishing predictable right-of-way scenarios. Therefore, vessel A is responsible for taking early and substantial action to avoid a collision.