What does a blue rectangular sign typically mean?

A blue rectangular sign indicates mandatory information that drivers must follow. In Belgium, such signs are commonly used to convey directives that require specific actions from drivers, such as speed limits, lane usage, or other traffic regulations. The blue background signifies that the information is compulsory and must be adhered to by all road users in order to maintain safety and compliance with traffic laws.

Understanding this helps drivers recognize the importance of obeying these signs, as failure to comply could lead to traffic violations or unsafe driving conditions. This differentiates blue rectangular signs from other colors and shapes that might serve different purposes, such as providing warning signals or recreational information. By knowing that blue signs indicate requirements, drivers can better navigate the road while ensuring they follow the necessary regulations.