What Do Road Signs Do to Promote Smooth-Moving Traffic?

If you’re not looking at your phone while driving (very dangerous behavior!), you’ll notice them almost everywhere on the street. Road signs dominate highways, stand at busy city intersections, and perch quietly beside rural roads.

And if you pay attention, you’ll receive important driving instructions or warnings of possible dangers on the road ahead. In short, road signs help move traffic along smoothly and provide valuable information that will keep you and your passengers safe.

On the contrary, ignoring them can be dangerous—not only to you but to your passengers, other motorists and pedestrians as well. And neglecting their instruction could result in a fine, bad traffic, an accident or, worse, the loss of lives.

Although you may not feel the need to pay attention to the signs dedicated to “truckers”, you might want to rethink that if you’re ever planning to move. What if you do not hire a mover? You’ll need to know what those signs mean then.

What is the purpose of road signs?

Road signs, in one form or another, have been around since the Roman Empire. Today, they are the most commonly used traffic control device for managing, protecting and speeding up traffic. Their goal is to maintain the order and safety of everyone on the road—motorists and pedestrians alike.

Since we assume that anyone driving a vehicle knows the basic rules of the road, road signs are used to convey specific regulations, to provide warnings or hazards that are not obvious, and to relay other important information or guidance to motorists (such as your location or where services are located).

Road signs come in different shapes and colors, depending on the message they deliver. These colors and shapes have specific meanings and allow people to quickly identify and respond to them without any disruption to driving. Most road signs also use images that are easy to interpret or understand by everyone regardless of the language they speak. And if they include words, the message is always simple and clear. 

Since they relay important information that keeps everyone on the road safe and protected from accidents, road signs are placed in a prominent location that commands the attention of motorists and pedestrians. They are also positioned in ways that provide people enough time to act on their message.

What controls the movement of traffic?

3 Things Road Signs Do to Encourage Smooth Traffic Flow

Road signs basically have three functions: regulate, warn and guide.

Regulate Traffic Flow 

Regulatory/Regulation Signs are used to inform motorists of traffic laws or regulations about speed, lane use, turning, traffic direction, parking and other special situations. Standard regulatory signs are written notices of regulations. Some regulation signs—a red circle with a red slash over a symbol—prohibit people from doing something (e.g., No Parking, No U-Turn, etc.). Other regulatory signs are rectangle white signs with red or green letters.

Other examples of regulatory signs include: 

  • Speed limit signs – shows the maximum or minimum safe speed allowed
  • Stop sign – instructs motorists to stop and wait for crossing vehicles and pedestrians to clear
  • One way – traffic is moving in one direction only (denoted by an arrow)
  • Lane control signs – typically uses an arrow and located along or above the road; indicates where motorists can go or turn
  • Passing signs – tells motorists where passing is safe and allowed
  • Yield sign – tells motorists to slow down and yield right of way
  • Wrong way – indicates you have entered a lane of oncoming traffic after making a wrong turn
  • Do not enter – typically located on one-way roads or at exit ramps; it means you cannot enter

Warn of Potential Hazards or Other Special Situations 

Warning Signs are typically yellow diamonds with black letters or symbols. They call motorists’ attention to a special situation or hazard (actual or potential) on the road ahead or on the adjacent street, so they need to slow down or stop if necessary.

Examples of warning signs include: 

  • Pedestrian crossing – people cross the street here so watch out for them
  • School crossing – reduce your speed and watch out for school children crossing the road
  • School bus stop ahead – you’re nearing an area where a school bus is picking up or dropping school children
  • Ramp speed – indicates the recommended speed on an exit ramp
  • Slippery when wet – slow down during wet weather
  • Intersection/Crossroad – watch out for traffic from the intersection or crossroad up ahead
  • Hill – the road ahead goes down a hill, so check your brakes
  • Deer Crossing – slow down and watch out for any deer crossing the road
  • Farm machinery – be ready to slow down for any farm equipment crossing the street
  • Merging traffic – other vehicles will be blending into the main road ahead

Guide Motorists

Guide Signs designate location, direction or route markers. They help you plan your trip and perform four functions: 

  1. Provide directions, 
  2. Inform motorists of intersecting routes, 
  3. Direct motorists to cities and other important destinations, and
  4. Give guidance to available service, points of interests, and cultural, recreational, or other geographical sites.

Based on these functions, these road signs are further classified as: 

  • Guide signs – Square or rectangular in shape that are either green or brown with white letters; they denote direction and distance to destinations, such as cities, airports, museums, natural parks, and historical areas
  • Service signs – Blue square or rectangular signs with white letters or symbols; they indicate where rest areas, gas stations, hospitals, campgrounds, and other services are located
  • Route signs – Have different shapes depending on road type. Examples include:
    • U.S. and state routes are black squares with white markers. 
    • Interstate highways are red, white, and blue shields with even or odd two-digit numbers. Even-numbered roads run from east to west, while odd-numbered roads run from north to south.
    • County routes are indicated by a blue-and-yellow pentagon sign.

Follow Road Signs and Keep Traffic Moving

Now that you know what road signs do to promote smooth-moving traffic and more, look out for them while driving. (Don’t be distracted by your phone!) Pay close attention to their instructions while on the road—whether on multi-lane highways, busy city streets, or quiet country roads—to keep yourself and your passengers safe. Your loved ones, other motorists and pedestrians will thank you for it.