Includes postal services and voice mail.
- Postal services - the services used to transmit physical objects and tangible letters across space
- Voice mail - a computer based system that allows users to exchange voice messages
This category has the following 2 subcategories, out of 2 total.
Pages in category "Message systems"
The following 2 pages are in this category, out of 2 total.
Media in category "Message systems"
This category contains only the following file.
- Message Systems Mors...