There are many alphabet systems used to send messages throughout history. The most relevant and recent one would be known as Morse code. Any language's alphabet can be used to send messages as well.
No. Pigeons are no longer needed to send messages in combat.
invisable ink
Partoonship
It was an early form of electronic communication where Morse Code was used to send messages by wire.
1861
nerves system
Both the nervous system and the endocrine system send messages to the brain
no??
Hermes
they invented maths because the needed to some how figure out the ways of life. they invented the alphabet because the needed to send messages to each other.
They send messages to the spine from their brain.
nerves send the messages that make muscles move
nerves send the messages that make muscles move
SPINAL?
Committees of Correspondence
It goes through your neurons up to your brain
'Send messages' in French is 'envoyer des messages'.