What does an octagonal (eight-sided) red sign always mean?

An OCTAGONAL (eight-sided) RED sign ALWAYS means STOP. DMV/permit test. The unique octagon shape is reserved exclusively for stop signs — so it's recognizable even if covered by snow or hard to read. At a stop sign, come to a COMPLETE stop, yield to pedestrians and cross traffic, and proceed only when safe. SIGN SHAPES convey meaning: OCTAGON = stop; TRIANGLE (downward) = yield; DIAMOND = warning; RECTANGLE (vertical) = regulatory (speed limits, rules); PENNANT = no passing; PENTAGON = school zone; CIRCLE = railroad crossing. Knowing that the octagon always means stop is a fundamental, commonly tested sign concept.