Signs, Signals and Pavement Markings: Sign Shapes and Colors, Regulatory, Warning, Guide, Construction and Service Signs, Traffic Signals, Lane and Pedestrian Signals, Pavement Markings, Turn and Bicycle Lanes, and Roundabouts

Written for aiforu2 as the source for a practice-test bank and the on-device tutor for the Georgia driver's license knowledge exam. The facts follow the official manual; the wording is ours.

Source: Georgia Driver's Manual 2023–2024, Georgia Department of Driver Services (DDS), section 7 "Signs, Signals and Markings" (pp. 28–37).

It's the law

Every driver, including bicyclists, must obey official signs and signals unless a police officer or emergency worker directs otherwise. The road signs part of the knowledge exam asks you to identify signs, signals and markings, so learn them by shape and color first; you recognize a shape long before you can read the words.

The seven shapes

• Octagon (eight sides): always stop. Stop at the marked stop line; with no line, before the crosswalk; with no crosswalk, where you can best see traffic. Do not go until pedestrians on your side have finished crossing and you have yielded to close traffic.
• Triangle (point down): yield. Slow to a reasonable speed, stop if necessary at the stop line, and give way to vehicles in the intersection or approaching closely.
• Round: a railroad crossing is ahead, posted a few hundred feet before the tracks; slow, look, listen, roll a window down if needed, and stop if a train is coming. Never try to beat a train, and passing is prohibited at all railroad crossings.
• Pentagon (five sides): a school zone or school crossing, placed 150 to 700 feet before the school grounds or crossing; sometimes fluorescent green.
• Diamond: warning of an existing or possible hazard, yellow with black words or symbols.
• Vertical rectangle: regulatory, telling you what you must do, with the force of law.
• Horizontal rectangle: guide signs showing locations, directions and other information.

Regulatory signs

Regulatory signs say what you may or may not do, and bicyclists must obey them too. A red circle with a slash from upper left to lower right means "no": the picture inside shows what is prohibited (no left turn, no U-turn, no right turn, no bicycles, no trucks). Do Not Enter marks a one-way road or ramp you may not drive on; Wrong Way means traffic is coming toward you and you must not continue; One Way allows travel only in the arrow's direction; Keep Right sends traffic right of a median or obstruction; Slower Traffic Keep Right tells slower drivers to use the right lane; Speed Limit gives the maximum; Reduced Speed Ahead and School Speed Limit warn that a lower limit is coming or is in force while the lights flash; No Turn on Red forbids the turn even after a full stop.

Warning signs

Usually yellow with black (sometimes fluorescent green), warning signs alert you to conditions immediately ahead that may require action: sharp turn, curve, reverse turns, winding road, side road, side road at an angle, crossroad, T intersection (the road ends; slow and prepare to yield or stop before turning), narrow bridge (room for only two lanes), dip, bump, soft shoulder (drive on it only in emergencies), divided highway begins or ends, two-way traffic ahead, low clearance (do not enter if your vehicle or load is taller than shown), steep hill (slow and be ready to shift down to protect the brakes), signal ahead, yield ahead, stop ahead, slippery when wet (the first half-hour of rain is the most hazardous), no passing zone (the pennant on the left side of the road, where any pass must already be finished), merging traffic, lane ends, pedestrian crossing (stop and stay stopped while pedestrians are in the crosswalk), and animal, people or vehicle crossings. Warning signs may carry an advisory speed plaque giving the speed at which to proceed.

Guide, construction and service signs

Guide signs tell you what road you are on and how to reach your destination: route markers (interstate shields, U.S. and state routes), exit numbers, destination and distance signs, bicycle route signs, mileposts placed every mile from the south or west border where a route begins, and parking area signs. A slow-moving vehicle emblem (orange triangle) marks a vehicle going under 25 mph. The crossbuck stands at every railroad crossing: yield to trains, and a plaque below gives the number of tracks; a complete stop is required when the red light flashes.

Construction and maintenance signs are orange with black and give you time to slow for road work ahead. Service signs are blue and white and point to food, phone, gas, lodging, hospitals and camping. Express Lanes signs mark tolled lanes that need a registered Peach Pass: the I-85 Express Lanes in Gwinnett County are open 24 hours and free to registered transit, three-or-more-person carpools, motorcycles, emergency vehicles and alternative-fuel vehicles with the AFV plate; the reversible I-75 South Metro Express Lanes in Henry and Clayton counties charge everyone except transit buses, registered vanpools and emergency vehicles with a Peach Pass.

Traffic signals

Drivers, bicyclists and pedestrians obey signals unless an officer directs traffic. A signal that is completely dark is treated as a stop sign for all directions. A flashing signal is obeyed by color: flashing yellow, proceed with caution; flashing red, stop completely as at a stop sign, then go when safe.

• Red: stop completely before the crosswalk or intersection and wait for green.
• Yellow: the light is changing to red; slow and prepare to stop.
• Green: go if safe, after stopping for pedestrians and yielding to vehicles still in the intersection.
• Green arrow: go carefully only in the arrow's direction after stopping for pedestrians and yielding to vehicles in the intersection.
• Yellow arrow: may follow a green arrow; clear the intersection.
• Flashing yellow arrow: you may turn left after yielding to oncoming traffic and pedestrians, because oncoming traffic still has a green light.

Lane control signals over reversible lanes: a green arrow means travel in the lane; a red X means no travel in that lane in your direction; a steady yellow X means clear the lane; a flashing yellow X means a left turn is permitted. Overhead lane signs show which movements each lane allows (left only, straight or left, right only). Pedestrian signals: a Walk symbol means leave the curb; a steady Don't Walk means do not leave the curb; a flashing Don't Walk means do not start, but finish crossing if you already have; a countdown shows the time remaining.

A Pedestrian Hybrid Beacon (PHB) stays dark until a pedestrian presses the button; then drivers see flashing yellow for a few seconds, then solid yellow (slow, prepare to stop), then double solid red (stop), then alternating flashing red (stop fully, then proceed once pedestrians have cleared the crosswalk), after which it goes dark again.

Pavement markings

• Stop lines: white lines across the pavement at intersections, in urban areas about four feet before the crosswalk; stop at the line, not at the sign or signal.
• Crosswalk lines: white lines across the road, sometimes a ladder pattern, sometimes mid-block; pedestrians in them have the right-of-way.
• Railroad crossings: a large X and two Rs on the pavement, always with a solid yellow line on the right of the center line to prevent passing; stop when the signals show a train.
• Center lines separate opposite directions; a broken yellow line on a two-lane road means passing is allowed either way when safe.
• No-passing lines: a solid yellow line on your side of the broken line forbids passing from your lane; two solid yellow lines forbid passing both ways.
• Double white lines: dashed, you may cross to the next lane; solid, lane changes are prohibited.
• Edge lines: solid white along the pavement edge, guiding you at night; a yellow edge line on the left warns of a narrow or raised median.
• Lane lines: white dashes dividing lanes going the same direction. With four or more lanes of two-way traffic, two solid yellow lines mark the center, crossed only to turn left into or out of an alley, driveway, private road or street; stay in the right lane except to pass.
• Traffic striping: diagonal yellow lines inside solid lines, shaped like a triangle, mark a narrowing road or an obstruction; keep right of them.
• Two-way left turn lanes: a center lane bordered by solid and broken yellow lines is for left turns only, entered no more than 300 feet before the turn, with extreme caution because opposing drivers use it too.
• Bicycle lanes: solid white lines between the rightmost lane and the curb, placed left of a right-turn-only lane; drivers may not drive or park in them and cross them only to turn, yielding to bicyclists.

Roundabouts

Roundabouts replace stop signs and signals to move heavier traffic. Traffic circulates counterclockwise; you always enter to the right and exit to the right. Approach at the posted advisory speed and stop for pedestrians in the crosswalk; yield to all vehicles already circulating, in both lanes at a multilane roundabout; wait for a gap and merge; keep circling until your road; signal, then bear right to exit, stopping again for pedestrians. In a multilane roundabout, follow the lane signs and arrows to pick your lane before entering and do not change lanes inside. Pedestrians cross to the refuge island in stages and never to the center island; confident cyclists ride in the middle of the lane, and others walk their bikes as pedestrians.

Practise this with Georgia Driver License questions

More of this guide