Bundesstraße
One distinguishing characteristic between German "Bundesstraßen" and "Autobahnen" is that there usually is a general 100 km/h (62 mph) speed limit on federal highways out of built-up areas, as opposed to the merely advisory speed limit ("Richtgeschwindigkeit") of 130 km/h (83 mph) in unmarked sections of the autobahns. However, a number of "Bundesstraßen" have been extended as expressways (dual carriageways) (colloquially called "Yellow Autobahns"). Many of these have speed limits of usually 100–120 km/h, others have only an advisory speed limit like autobahns. Most sections of the federal highways are only single carriageway with one lane for each direction and no hard shoulder pull-out area.
Advisory speed limit
Signposting of advisory speed limits varies from country to country; Australia makes extensive use of advisory speed limits across its highway networks while the "Richtgeschwindigkeit" ("reference speed") in Germany is valid for the whole autobahn network (but can be overruled by speed limits in particular sections or for special reasons like weather conditions or roadworks), while the United States and the United Kingdom only give advisory speed limits for hazards such as bends.