Where:
At intersections.

Purpose:
To allow traffic turning left, without having to stop completely.
Only if it can be done safely, and without interfering with cross traffic.

Action:
If you are driving straight through the intersection, you must stop completely behind the stop line.
If you are turning left, you may proceed without stopping, but only if it can be done safely.
Always yield to all approaching traffic and pedestrians that are close enough to pose a hazard.
Proceed only when it is safe to do so.