As someone who’s been around police officers and truck drivers, I’ve heard the phrase “10-4” many times. But what does it mean, exactly? Is it just a casual affirmation, or does it have a more specific use? After doing some research, I’ve found that “10-4” is actually part of a larger system of codes used by police officers and other emergency responders.
According to the Association of Public-Safety Communications Officials-International (APCO), “10-4” is one of the so-called “ten-codes” used in radio communication. “10-4” is an affirmative signal that means “OK” or “message received.”
These codes were invented in the late 1930s by Illinois State Police Communications Director Charles Hopper, and were designed to be used by law enforcement officers and other emergency responders to quickly and efficiently communicate with each other over the radio.
While the ten-codes were originally designed for use by police officers, they have since become more widely known and used in popular culture. You might hear someone say “10-4” in a casual conversation, or see it used in a movie or TV show.
It’s important to remember that these codes were created for a specific purpose, and that their use in everyday conversation can be confusing or even dangerous in emergency situations.
What is 10-4?
I am familiar with the meaning of 10-4. 10-4 is a ten-code, or radio signal, used by law enforcement, truck drivers, and other professionals to communicate quickly and efficiently. It is a simple way to acknowledge that a message has been received and understood.
The ten-codes were developed by the Association of Public-Safety Communications Officials-International (APCO) in the late 1930s. They were created to standardize radio communication among law enforcement officers and other public safety officials. 10-4 is one of the most commonly used ten-codes, and it means “message received and understood.”
When a message is received, the recipient will often respond with “10-4.” This is a copy, acknowledgement, and confirmation that the message has been received and understood. It is a quick and efficient way to communicate without using plain language.
While ten-codes were originally developed for use in radio communications, they have become part of everyday language for many people. 10-4 is often used in casual conversation to indicate agreement or understanding.
History of 10-4
As I researched the origins of 10-4, I discovered that it is part of a collection of ten codes developed by Illinois State Police communications director Charles Hopper in the late 1930s. These codes were designed to be used by police officers and other emergency responders to communicate quickly and efficiently over two-way radio systems.
The ten codes were initially developed to be used in Morse code, but they were adapted for voice communication as two-way car radios became more common. The codes were meant to convey information quickly and accurately, without the need for lengthy explanations.
One of the most well-known ten codes is 10-4, which means “understood” or “message received.” This code was first used by the Illinois State Police and quickly spread to other police departments across the country. It has since become a staple of police radio communication and is widely recognized by the general public.
While ten codes were once widely used by police and emergency responders, they have been largely replaced by plain language in recent years. This is due to variations in what the codes mean and the potential for confusion when communicating with other agencies that use different codes.
Truckers and other CB radio users still use ten codes, including 10-4, to communicate quickly and efficiently. The use of 10-4 has become so widespread among American police officers on police radio that it is sometimes referred to simply as “The Ten Four.”
The history of 10-4 is closely tied to the development of ten codes by the Illinois State Police communications director Charles Hopper in the late 1930s. While ten codes have largely been replaced by plain language in police and emergency responder communications, 10-4 remains a widely recognized and used code among truckers and CB radio users.
Usage of 10-4
I can tell you that 10-4 is a widely used code in radio communication. It is used to acknowledge receipt of a message or to indicate agreement. The code has been in use since the early days of radio communication and has been adopted by various groups, including law enforcement, truckers, highway patrol, pilots, and family radio service users.
In law enforcement, 10-4 is used to acknowledge receipt of a message or to indicate agreement. It is commonly used in police radio channels to confirm that a message has been received and understood.
For example, if an officer receives a message to respond to a particular location, they may respond with “10-4” to indicate that they have received the message and will respond accordingly.
Truckers also use 10-4 extensively in their communication, especially on CB radios. It is used to confirm receipt of a message or to indicate agreement.
For example, if a trucker receives a message to change lanes, they may respond with “10-4” to indicate that they have received the message and will comply.
Highway patrol officers also use 10-4 in their communication. It is used to acknowledge receipt of a message or to indicate agreement.
Example, if a highway patrol officer receives a message to respond to a particular location, they may respond with “10-4” to indicate that they have received the message and will respond accordingly.
Pilots also use 10-4 in their communication with air traffic control. It is used to confirm receipt of a message or to indicate agreement.
Example, if a pilot receives a message to change altitude, they may respond with “10-4” to indicate that they have received the message and will comply.
Family radio service users also use 10-4 in their communication. It is used to confirm receipt of a message or to indicate agreement.
If a person using a family radio service device receives a message to meet at a particular location, they may respond with “10-4” to indicate that they have received the message and will comply.
In radio communication, it is important to use the phonetic alphabet to ensure that messages are understood clearly. The phonetic alphabet is a set of words that are used to represent letters of the alphabet.
“A” is represented by “Alpha,” “B” is represented by “Bravo,” and so on. When using 10-4, it is important to use the phonetic alphabet to ensure that the message is understood clearly.
10-4 in Popular Culture
Throughout the years, the phrase “10-4” has been used in various forms of popular culture, including movies, TV shows, and music.
Here are a few examples:
- Smokey and the Bandit: This 1977 action-comedy film features trucker communications that use CB radio slang, including “10-4.” The movie popularized the use of CB radios and trucker slang in American culture.
- Broderick Crawford: The actor, famous for his role in the TV series “Highway Patrol,” helped popularize the use of “10-4” as a ten-code for “affirmative” or “understood.” His character, Dan Mathews, frequently used the phrase in the show.
- C.W. McCall: The country music artist released a song in 1975 called “Convoy,” which features truckers communicating with each other using CB radio slang, including “10-4.” The song became a hit and helped popularize the use of CB radio slang in American culture.
- Movies: The use of “10-4” and other CB radio slang can be found in many movies, including “Black Dog,” “Breaker! Breaker!,” and “White Line Fever.”
- Action movie: The use of “10-4” in action movies is often associated with police and military communication. It is used to indicate that a message has been received and understood.
- Trucker communications: Truckers use CB radio slang, including “10-4,” to communicate with each other on the road. This helps them stay informed about traffic, weather, and other important information.
The use of “10-4” in popular culture has helped to popularize the phrase and its meaning. It is now commonly used in everyday conversation to indicate understanding or agreement.
Similar Phrases to 10-4
When communicating over a two-way radio or CB radio, it’s important to use clear and concise language to ensure that messages are understood correctly. While 10-4 is a commonly used phrase to indicate that a message has been received and understood, there are several other phrases that can be used to convey a similar meaning.
One phrase that is often used in place of 10-4 is “affirmative”. This phrase is typically used to indicate agreement or acknowledgement of a message. Similarly, the phrase “understand” can be used to indicate that a message has been received and comprehended.
Another phrase that is similar to 10-4 is “sure”. This phrase is often used to indicate that a message has been received and that there is no problem with the content of the message. Similarly, the phrase “no problem” can be used to indicate that a message has been received and that there are no issues to report.
In addition to these phrases, there are several other terms that can be used to convey a similar meaning to 10-4. For example, the phrase “power” is often used to indicate that a message has been received and that the recipient is ready to take action. Similarly, the phrase “roger that” can be used to indicate that a message has been received and understood.
Overall, there are several different phrases that can be used to convey the same meaning as 10-4. By using clear and concise language, radio operators can ensure that messages are understood correctly and that communication is effective.