This system, the GPS - Global Positioning System was developped by the military as well. Today it is in use on every ship, small yachts and even in cars as well. Navigation is reduced to a simple look at different screens and to learn how to switch the electronic devices on and off. No longer of interest for the study of elder generations. Today you can buy sea charts for your personal computer and take it aboard.
Professional ships use fully electronical sea charts.
On this stamp you can see a display with an electronical chart. Then you have to change back to old methods of navigation. There are existing a lot of stamps and postal stationaries about navigation. Especially when you expand the theme to hydrographic offices, nautical schools, weather charts etc.