Category:Message systems

From ETHW

A 1916 photo of British officials using Morse Code at The Battle of Somme

Includes postal services and voice mail.

Subcategories

  • Postal services - the services used to transmit physical objects and tangible letters across space

Subcategories

This category has only the following subcategory.

Media in category "Message systems"

The following 2 files are in this category, out of 2 total.