More text revision
'''Big Caveat''': Google has completely deprecated a technology called NPAPI in Chrome, Firefox has also reduced support for NPAPI with the ultimate goal of removing it. This technology is required to run plugins like Silverlight, Java and others. Many of the links below will require you to allow these plugins to run, so you may need to open Internet Explorer or Safari to run them.
The [http://portal.gis.ca.gov/geoportal/viewer/index.jsp California Geoportal Viewer] is an all-state viewer, with only a Roads layer. It is very quick and easy to use, but may not be quite as up to date as local maps, though it is usually more accurate on road names than Caltrans Earth. Geoportal requires Silverlight to
[http://earth.dot.ca.gov/ Caltrans Earth] contains a wealth of layers. <span style="color:#F00000">Note: as of September 2015, Caltrans has posted a message, recommending the use of Internet Explorer 11. As of April 2016, Safari works, as well. </span> Of these, the most useful to Waze Map Editing currently include: Roads (see caveat above), Functional Classification, Cities, Counties, Highway Exit Numbers, Railroads and Airports, Park and Ride lots and Rest Areas. Also of limited use: Lane Closures (FAR from comprehensive), CHP Incidents, Traffic Cams and Highway Message Signs (current message can be displayed), and certain Caltrans projects (again, FAR from a complete listing). These last four are also displayed on the Caltrans Quick Map, which is accessible from most browsers, and also from a Mobile App. Caltrans Earth requires installation of the Google Earth plugin, currently available only on Apple and Windows platforms.
''Note: In most cases, the links below will land you on the map itself, but sometimes it is is necessary to accept a disclaimer before viewing the map. A few maps require the use of Internet Explorer (noted), others require installation of the Silverlight plugin, and still others require an Autodesk plugin. Where there is no ''County'' interactive viewer, static map pages are linked and so indicated (I hope, let me know) by italics. A few counties do not yet publish online maps; use the Geoportal Viewer for these. ''
Above all, understand that map availability is constantly changing. If you don't see what you're looking for here, try a search for "GIS" and the location you're looking for; it's quite possible there's a map now. And if you find one, let me know, so I can add it!
Thanks to users '''ababcock, AquaZR1, bwawsc, citeman, Cardyin, robertonthego''' for contributing! (Anyone I've missed? Please let me know)