10-4 or Code 404? See How Well You Know Police Lingo and Terms
What does the police code "10-4" mean?
Correct Incorrect "10-4" is a radio code used by police to say they got the message and understand it. It started in the 1930s to make radio talk quicker and clearer. Even though some departments now use plain language, "10-4" is still widely known thanks to movies and TV.