The sign you mentioned is a Pedestrian Underpass sign. This sign indicates that there is a pedestrian underpass available for crossing the road safely, minimizing the risk of accidents with vehicles. It informs drivers to be cautious as pedestrians may be using the underpass, and it also encourages pedestrians to use the designated pathway for their safety. Always be aware of this sign when driving, as it helps ensure the safety of both pedestrians and drivers alike. If you have more questions about traffic rules or other signs, feel free to ask!