Final answer:
A protected left turn allows vehicles to make a left turn without interruption from oncoming traffic, thanks to a dedicated traffic signal, usually in the form of a green arrow.
Step-by-step explanation:
A "protected" left turn means for vehicles in traffic that they are permitted without interruption by other traffic flows. Specifically, when a turn is indicated as protected, typically by a green arrow light pointing to the left, it signifies that oncoming traffic has a red light, and vehicles turning left have the right-of-way. This type of turn is designed to maximize safety at intersections, avoid conflicts with opposing traffic, and streamline the flow of vehicles.