Editing Variable-message sign (section)

{{Short description|Electronic traffic sign with changeable messages}}
{{more citations needed|date=May 2015}}
[[File:MN Changeable Message Sign.jpg|thumb|[[Dot-matrix display|LED matrix]] sign over [[Interstate 94|I-94]] in [[Saint Paul, Minnesota]], advising of a road blockage during a winter storm]]
[[File:New Jersey Turnpike Reduce Speed sign.jpg|thumb|Early style of VMS on the [[New Jersey Turnpike]] using [[Neon sign|neon tubes]], since replaced by new LED VMS signs. It is next to a vane variable speed-limit sign]]
[[File:Verkehrsleitsystem Nuernberg 1.JPG|thumb|Europe's largest Dynamic Route Guidance System [[Nuremberg]], Germany]]
[[File:Illinois Tollway - Digital Signage (45706130121).jpg|thumb|[[LED display|LED]] sign over [[Interstate 90 in Illinois|I-90]] (Jane Addams Memorial Tollway) in [[Riley Township, Illinois]], showing remaining travel times]]
[[File:MÚK Lahovice, směrové tabule před odbočením na Lochkov.jpg|thumb|Mechanical variable-message sign (right) on the [[D0 motorway (Czech Republic)|Prague Ringway]], Czech Republic; made by Značky Praha s.r.o.]]
A '''variable-''' (also '''changeable-''',<ref>{{Cite web |url=http://epg.modot.org/index.php?title=616.3_Changeable_Message_Signs_%28CMS%29 |title=616.3 Changeable Message Signs (CMS) - Engineering Policy Guide<!-- Bot generated title --> |access-date=2007-12-24 |archive-date=2012-03-11 |archive-url=https://web.archive.org/web/20120311183139/http://epg.modot.org/index.php?title=616.3_Changeable_Message_Signs_%28CMS%29 |url-status=dead }}</ref> '''electronic-''', or '''dynamic-''') '''message sign''' or '''message board''', often abbreviated '''VMS''', '''VMB''', '''CMS''', or '''DMS''', and in the UK known as a '''matrix sign''',<ref>
{{citation |url=http://www.opsi.gov.uk/si/si1994/Uksi_19941519_en_2.htm#mdiv36|title=The Traffic Signs Regulations and General Directions 1994|publisher=[[Office of Public Sector Information]]|year=1994|access-date=2008-04-05}}</ref>
is an electronic [[traffic sign]] often used on [[road]]ways to give travelers information about special events. Such signs warn of [[traffic congestion]], [[traffic safety|accidents]], incidents such as terrorist attacks, [[AMBER Alert|AMBER]]/[[Silver Alert|Silver]]/[[National Blue Alert Act of 2013|Blue]] Alerts, [[construction|roadwork zones]], or [[speed limit]]s on a specific highway segment. In [[urban area]]s, VMS are used within [[parking guidance and information]] systems to guide drivers to available car parking spaces. They may also ask vehicles to take alternative routes, limit travel speed, warn of duration and location of the incidents, inform of the traffic conditions, or display general public safety messages.