10/04/2026
Most people say "10-4" without knowing where it comes from.
The ten-codes were created in the 1930s - not for truckers, but for law enforcement. Radios back then needed time to warm up before transmitting, so starting every message with "ten" gave the signal time to reach full power before the actual code came through.
Truckers picked them up in the 1960s and made them their own. By the 1973 oil crisis, CB radio was essential on every rig, drivers using codes to share which gas stations were open, where speed traps were, and how to avoid traffic.
10-4 - Message received.
10-9 - Say that again.
10-20 - Where are you?
10-33 - Emergency, clear the channel
10-100 - Bathroom break.
A whole language, built for the road.
Happy National 10-4 Day to everyone who keeps freight moving. π»π