We all know that traffic signs do an important job: they tell us what exactly we can or can’t do on the road. But what if the signs were confusing? Sometimes this leads to funny stories afterwards, other times it leads to tragedy, as a misunderstood sign may sometimes lead to crashes.

These signs, wherever state they may show up, must be approved by the Manual on Uniform Traffic Control Devices (MUTCD). They create the standard by which all signs could be installed, maintained, and managed by road managers everywhere. The MUTCD is published by the Federal Highway Administration (FHWA).

Here then, is a list of some of the more … confusing traffic signs that are currently out there.

Yield – The red upside-down triangle sign, or sometimes, a simple verbal instruction to “YIELD”? It’s surprising just how many people get confused with this sign. The best way to describe it is it’s like a lighter version of the STOP sign. When faced with this sign, motorists should stop, give way to vehicles from another approach and then enter an intersection. These usually appear in smaller roads that don’t get enough traffic that they don’t necessarily need a STOP sign.

Runaway Vehicles Only – But what if you weren’t running away? This sign signifies that a runaway device is installed in an area. This is usually for trucks that have lost control — the device is usually a patch of road with sand or gravel, which helps vehicles come to a safe stop. The gravel or sand allows the momentum of the big vehicle to dissipate, allowing for safe stopping.

This Side of Sign – This sign signifies that something is allowed on “this side” or the side where the sign is installed. A variation of this sign may say “Parking This Side of Street.” This means that one may only park on that specific side and parking elsewhere may give you a parking ticket.

To Request Green Wait On [Bicycle symbol] – Blame it on confusing wording. This sign is supposed to give bikers a green light. This sign should be used in conjunction with traffic actuators that are adjusted to the amount of metal a bicycle has. If you’ll notice, there is a vertical line going on the top and bottom of the bicycle symbol. This means that bikers should position themselves in the designated marking for them to be detected by the actuators, giving them a green light. Some people confuse this as waiting for bicycles to ride by until they can get a green light.

Look <—-> – Looking left-to-right? Isn’t that what parents and preschool teachers teach kids before crossing the road? This sign is usually located near railways, signifying that motorists should be on the lookout for trains from both directions.

Truck Rollover – Nope this sign doesn’t signify the truck-wheelie lane — it only means that there is a slope nearby that truck drivers should be aware of, since there’s a big tendency for their vehicles to rollover.

Circular Intersection – Though it bears a striking resemblance to the recycling sign, this sign simply signifies that a circular intersection is coming up. Some circular intersections are different. In some cases, the entering vehicles have the right-of-way, while the vehicles inside the circle must yield. Sometimes this is reversed, so drivers have to do a bit of research before they go right through.

Stop Ahead – Stop vertically? No — this is simply a sign that signifies that there will be an oncoming stop. A sign for a sign, perhaps?

9% Grade – The roads aren’t trying to quantify your reading level or your abilities with math. This only means that there is an oncoming 9% Grade slope. Slopes on the road are measured in grades: consider that 9% is 9-feet off a hundred. It means that elevation may change from 5 (5% Grade) to 9 (9% Grade) feet.

DIP – Motorists have to wonder: how exactly are they going to “dip” their cars? This simple sign that says “DIP” means that there will be a dip in the road: parts of the road may go down, and then elevate right back up again.

Having trouble with learning the Roads of the Road and Traffic Signs? Take a DMV Practice Test to become an expert and pass your DMV written exam the first time.