PlayInfoBox

Home /Education /A Dictionary of Road Traffic Sign Types: Warning, Regulatory, and Instruction Signs

A Dictionary of Road Traffic Sign Types: Warning, Regulatory, and Instruction Signs

Yellow triangles, red circles, blue circles — knowing just the shape and color of a sign can help you guess its meaning.

School zone sign — Warning signs (yellow triangle background)

A warning sign indicating the presence of a school zone (child protection zone) nearby. The speed limit is often lowered to 30 km/h or below in the surrounding area, and enforcement is frequently stepped up during certain hours.

Falling rocks sign — Warning signs (yellow triangle background)

A warning sign commonly seen in mountainous or excavated-slope sections, warning in advance that rocks may fall from above. It is generally advised to pass through such sections quickly rather than stopping or slowing down.

Slippery road sign — Warning signs (yellow triangle background)

A warning sign posted ahead of sections prone to slipping, where the road surface may be icy or prone to pooling rainwater. It frequently appears in shaded sections during winter or on bridges.

Traffic signal ahead sign — Warning signs (yellow triangle background)

A warning sign posted before locations where a traffic light might not be easily visible, such as on a curve or in a section with limited visibility, indicating in advance that a signal is installed ahead.

Road work sign — Warning signs (yellow triangle background)

A warning sign indicating that road construction is underway ahead, advising drivers to slow down and pay attention to safety. It is typically placed alongside traffic cones or safety fencing before and after a construction zone.

No thoroughfare sign — Regulatory signs (white background, red circle border)

A regulatory sign that prohibits passage entirely, for both pedestrians and vehicles, or for whichever group is specified on the sign. It is also used to temporarily block off a construction zone or accident site.

Do not enter sign — Regulatory signs (white background, red circle border)

A regulatory sign, shown as a white horizontal bar inside a red circle, indicating that vehicles cannot enter in that direction. It is commonly installed at the exit side of a one-way street to prevent driving against traffic.

No parking or stopping sign — Regulatory signs (white background, red circle border)

A regulatory sign, shown as a red circle with a diagonal line through it, indicating that both brief stopping and parking are prohibited in that section. Supplementary signs specifying the exact hours or days often appear below the main sign as well.

Maximum speed limit sign — Regulatory signs (white background, red circle border)

A regulatory sign that displays, as a number inside a red circle, the maximum speed (km/h) allowed in that section. The speed limit is set differently depending on the type of road and the characteristics of the section.

Straight-ahead-only sign — Instruction signs (mostly blue circle or square background)

An instruction sign, shown as an upward-pointing arrow inside a blue circle, indicating that the lane may only be used to go straight. Different instruction signs for each lane are often installed together before entering an intersection.

Crosswalk sign — Instruction signs (mostly blue circle or square background)

An instruction sign, shown as a walking person on a blue background, indicating that there is a crosswalk ahead where pedestrians may cross. It is installed together with white stripes painted on the road surface (crosswalk markings).

Bike-only lane sign — Instruction signs (mostly blue circle or square background)

An instruction sign, shown as a bicycle on a blue background, indicating that the section is designated exclusively for bicycle travel. A separate combined bicycle-and-pedestrian sign is used for sections shared by both.

U-turn sign — Instruction signs (mostly blue circle or square background)

An instruction sign, shown as an arrow curved into a U-shape inside a blue circle, indicating that a U-turn is permitted in the designated section. It's safest to also check for a separate U-turn traffic signal or a U-turn arrow marked on the road surface.

Why do traffic signs have different shapes and colors?

Traffic laws generally categorize signs into warning signs (yellow triangle background), regulatory signs (white background, red circle), instruction signs (mostly blue circle or square background), supplementary signs, and road surface markings. Many countries follow broadly similar principles internationally, so that a driver can quickly tell the general meaning of a sign — a hazard warning, a prohibition, or guidance — just from its shape and color, even from a distance.

What if you drive past a sign without noticing it?

If you're curious about the fines involved when an actual violation occurs, such as speeding or running a red light, take a look at our complete overview of traffic signal violation fines as well.

Frequently Asked Questions

What's the difference between a supplementary sign and a road surface marking?

A supplementary sign is a smaller, rectangular sign attached below a main sign that adds further detail, such as distance, time, or the section it applies to, while a road surface marking refers to markings painted directly onto the road surface itself, such as a stop line or a crosswalk.

Do sign shapes differ by country?

Broadly speaking, the general distinction between triangles (warning), circles (regulatory or instructional), and rectangles (supplementary or informational) is used similarly in many countries, but the specific design and color regulations can differ somewhat depending on each country's traffic laws.