you are colourblind.
Road construction signs are normally orange in color with black print. They warn drivers of road closings, upcoming stops, and detours.
Ranch Road
The black octagon is significant in traffic signs as it is used exclusively for stop signs. This shape and color combination is easily recognizable by drivers, indicating the need to come to a complete stop at an intersection for safety and traffic control purposes.
it indicate the road =way signs
Watch out for trees.
Gray
Round signs give orders, normal triangle signs give warnings and rectangular signs give useful information (the background colour of these describes the road by the way).
To My Knowledge
Folks On Spokes. It's a bike trail.
Changed road conditions
Road signs give information, warnings and instructions.
In the US, road signs in blue generally denote the presence of certain facilities. Some of the better-known ones include the "food-gas-lodging" signs telling you you can obtain those things at a particular exit, and the white H on a blue background sign that denotes a hospital.