Common Signs on the Road

On our way to Slippery Rock I saw some signs on the road that made me curious what those signs means so, i took pictures of them while the car was running.

These are common signs we see on the road which helps driver and pedestrian keep away from any accidents and traffic.

I took this signs in front the building of our old apartment. There is a school closer to our place and a playground for kids thats why they put signs like that for the drivers to slow down.
A stop sign is a traffic sign, usually erected at road junctions, that instructs drivers to stop and then to proceed only if the way ahead is clear.
Some traffic signs, such as the left-turn prohibition sign hanging from this gantry, are lit for better visibility, particularly at night or in inclement weather.
In road transportaton, a Yield (Canada, Ireland, and the United States) or give way traffic sign indicates that a driver of a vehicle must slow down and prepare to stop if necessary (usually while merging into traffic on another road) but does not need to stop if there is no reason to. A driver who has actually stopped in this situation is said to have yielded the right-of-way to through traffic on the main road. In contrast, a stop sign always requires a full stop. The first yield sign was installed in Tulsa, Oklahoma and was invented by Tulsan Clinton Riggs.
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