What is "greaseboards"

Usage examples of "greaseboards".

Up onstage, old-fashioned greaseboards and mark-and-erase maps and flow charts, updated by communications technicians with tissue paper and grease pens, dwarfed a few electronic computer screens.

As they watched, Korean technicians were busily rolling out huge mounted charts and large transparent greaseboards, setting up for monitoring the emergency the old-fashioned way, before computerized maps and real-time data feeds.

Technicians started carrying out sound-powered communications systems, simple Korean War-era field telephones, and old-style greaseboards to replace the now-dark digital information screens.