A list of street sign meanings can be found in the Federal Highway Administration's "Standard Highway Signs and Markings" manual. To access the list, navigate to FHWA.DOT.gov, hover over the "Resources" tab and select "Core Highway Topics" from the drop-down menu. From there, click on the "Manual on Uniform Traffic Control Devices (MUTCD)" link under the "Road Operations and Congestion" heading.
The US. Department of Transportation's Federal Highway Administration is tasked with regulating roadways in the United States. The MUTCD and supplemental signs list published by the agency are updated as needed to ensure visitors get the latest and most up-to-date information.
Road signs convey meaning in multiple ways. The shape of the sign, its color and text or graphics displayed on it are all ways of communicating the rules of the road. For instance, rectangular signs are reserved purely for information. Other signs can have more or less sides depending the risk of a forthcoming intersection or other potential hazard. For instance, yield signs have 3 sides to signify low risk, but stop signs have 8 to convey higher risk.