I give advice to others, yet I know nothing myself. I am a hitchhiker destined to stay still while others pass by me. What am I?

This riddle cleverly describes an everyday object that plays a crucial role in our daily lives without ever moving or possessing consciousness. The "advice" it offers comes in the form of a posted speed limit, a silent directive telling drivers the maximum safe speed for a particular stretch of road. Despite this clear guidance, the sign itself "knows nothing," being an inanimate object devoid of thought or understanding.

The second part of the enigma, being a "hitchhiker destined to stay still while others pass by," perfectly illustrates its static nature. Positioned firmly on the roadside, these signs are permanent fixtures. They observe countless vehicles, acting as silent sentinels while the world rushes past them, adhering to or sometimes disregarding their vital instructions. This stillness is fundamental to their purpose, as they must be consistently visible to fulfill their regulatory function.

Speed limits and the signs that display them are essential for maintaining road safety and order. The concept of regulating vehicle speed emerged with the advent of automobiles, as early cars were capable of speeds far exceeding those of horse-drawn carriages, leading to new dangers. Over time, standardized signage, including the familiar circular speed limit signs, developed globally to ensure universal understanding and promote safer driving environments for everyone. They are a constant reminder of our shared responsibility on the road.