10-4 Meaning: What Does “10-4” Mean?

Last Updated on November 6, 2023

The term “10-4” holds a significant place in radio communication, particularly among law enforcement officers and truck drivers. Originating from the ten-codes developed by Illinois State Police Communications Director Charles Hopper in the late 1930s, 10-4 is used as an affirmative signal, meaning “OK” or “understood.” These codes were created to streamline conversations and ensure efficient communication over radio channels.

Over time, 10-4 has transcended its original purpose and has become ingrained in popular culture and everyday language. The public’s exposure to this code began in the 1950s through the television series Highway Patrol, starring Broderick Crawford. Since then, its use has expanded beyond law enforcement and radiotelephony and can now be found in various media and day-to-day conversations.

Key Takeaways

  • 10-4 is an affirmative signal, meaning “OK” or “understood,” commonly used in radio communication.
  • The code originated from the ten-codes developed by the Illinois State Police in the late 1930s.
  • 10-4 has become popular in everyday language and media, extending its reach beyond its original purpose in law enforcement and radio communication.

10-4 Meaning

Meaning and Usage of 10-4

10-4 is a widely recognized code in two-way radio communication to convey affirmative or a confirmation, meaning “OK” or “understood.” It is used by law enforcement agencies, truck drivers, CB radio users, and other communication channels where brevity and clarity are essential. In essence, when someone says “10-4,” they are indicating that they have received the message or information and understand it.

Meaning and Usage of 10-4 Pin

Origin and Context of 10-4

The origin of 10-4 can be traced back to the late 1930s when Charles Hopper, the communications director for the Illinois State Police, developed a series of ten-codes to streamline radio communication. These codes, including 10-4, were created to minimize confusion and misinterpretation of messages being transmitted over radio channels. The Association of Public-Safety Communications Officials-International (APCO) later adopted these codes, leading to widespread use.

The use of 10-4 and similar ten-codes expanded beyond law enforcement, as truck drivers, Citizens’ Band (CB) radio users, and others adopted them for their own communication purposes. While the meaning of ten-codes can vary slightly between jurisdictions and locations, 10-4 has remained consistent as a way to acknowledge a message has been received and understood.

Related Terms to 10-4

  • Roger: Another term used to convey affirmative or agreement, often interchangeable with “10-4.” It originated from aviation and military radio communication.
  • Message received: A phrase used to acknowledge understanding of the information shared. “10-4” serves as a shorthand way to express this.
  • Affirmative: A commonly used term across different communication platforms, meaning “yes” or “confirmed.” “10-4” is often used in place of “affirmative” for brevity in radio communication.
  • Out: In radio lingo, “out” is used to signify the end of a transmission and that the sender is not expecting a reply.
  • Call: Refers to a specific radio message exchanged between parties. “10-4” acknowledges the receipt and understanding of a call, removing the need for verbose confirmation.

While 10-4 has become synonymous with “OK” and “understood” in radio and CB communication, it is essential to know and utilize the appropriate set of ten-codes and radio communication terms depending on the context, jurisdiction, and industry to ensure clear and accurate exchanges of information.

10-4 in Popular Culture and Slang

10-4 is a term that has transcended its technical origins and found its way into popular culture and slang. Originally, 10-4 was one of the ten-codes, specifically radio signals, invented by the Association of Public-Safety Communications Officials-International (APCO). In this context, it means “message received” or “understood.”

Over time, the use of 10-4 has expanded beyond radio communications to become associated with various aspects of popular culture. One significant source of exposure was the 1950s television series Highway Patrol, where the protagonist, played by Broderick Crawford, would often use “10-4” while communicating with his patrol car’s microphone.

Truckers have also adopted 10-4 as part of their CB radio lingo, using it to confirm that they have received and understood a message. In this context, 10-4 has come to signify affirmation or agreement, similar to the casual use of “you got it” or “roger that.” Additionally, the phrase has worked its way into movies and songs connected to trucking culture, such as the 1975 film and song titled “Convoy.”

The widespread use of 10-4 in various mediums has contributed to its recognition and understanding by the broader public. Although still primarily associated with truckers and CB radio, the phrase has become part of colloquial language and is often employed in situations where a quick affirmation is needed. This linguistic evolution showcases the power of popular culture to shape our language and the way we communicate.

10-4 Synonyms

10-4 is a brief, commonly used term in radio communication that signifies acknowledgement and understanding. It is part of the ten-codes, a set of signals used in two-way radio conversations, particularly in the fields of public safety and emergency communication. These codes were created by the Association of Public-Safety Communications Officials-International (APCO) to quickly and efficiently convey important information among the personnel.

There are several other terms and phrases that share a similar meaning with 10-4. They can be used interchangeably in certain situations to express agreement or confirmation. Some of these synonyms include deal, pact, reconciliation, accordance, and concord. However, it is important to note that these terms might not be as universally recognized as 10-4 in the context of radio communication.

Another ten-code, 10-10, is used to indicate that a unit is available for another assignment or for further instructions. This code is related to 10-4, as it also serves to acknowledge the receipt of a message. However, the meanings are distinct enough that they should not be used interchangeably.

Radio communication often requires the use of concise, clear signals to ensure quick information exchange. For instance, if the message is not clear, a user might request a repeat of the information. In some cases, alternatives to ten-codes have been adopted by certain agencies and organizations to avoid confusion. These alternatives may use different codes or verbalizations for acknowledgement and other important messages.

In conclusion, while there are numerous synonyms for 10-4 that convey a similar sense of agreement and understanding, it is important to remember that 10-4, as a part of the ten-codes, holds a specific place in radio communication. Using the most appropriate term, whether it is 10-4 or one of its synonyms, is essential in ensuring clear and efficient communication.

Ten-Codes and Radio Communication Procedures

Ten-codes, also known as ten signals, are brevity codes used to represent common phrases in voice communication. They are often utilized by law enforcement, Citizens Band (CB) radio transmissions, and highway patrol units throughout the United States. Developed by the Association of Public-Safety Communications Officials-International (APCO), these codes facilitate efficient and concise communication among officers and other radio users, such as truck drivers.

One widely used ten-code is “10-4,” which stands for “Affirmative,” “Understood,” or “Message received.” This short, standardized response ensures clear and quick information exchange during radio transmissions. When officers are on the move or attending to emergency situations, the use of such codes can save time and improve communication clarity.

Aside from “10-4,” there are several other ten-codes used to convey different types of messages or information. For instance, “10-5” directs officers to relay a message to a specific person, while “10-6” signifies that they are busy and unable to immediately respond. In situations with poor radio reception, officers may use “10-1” to indicate that they are struggling to hear the transmission clearly.

The use of ten-codes is not limited to law enforcement agencies. CB radios, popular among truck drivers, also employ these codes in their day-to-day communication. Just like with police officers, truck drivers rely on these concise messages to convey important information such as their location or other related details.

It is essential for those working in law enforcement or using CB radios to be familiar with the standard ten-codes and their meanings. This knowledge ensures clear and efficient communication, reducing the likelihood of misunderstandings or misinterpretations during crucial operations or while conveying important information over radio transmissions.

FAQs Related to 10-4

What is the origin of the phrase “10-4”?

10-4 is part of a collection of “ten-codes” developed by Illinois State Police Communications Director Charles Hopper in the late 1930s. These codes were created to simplify and standardize radio communication among law enforcement officers who were using two-way car radios at the time. The phrase 10-4 translates to “understood” and became widely recognized through popular television series such as Highway Patrol, starring Broderick Crawford.

How is 10-4 used today?

Although 10-4 remains a popular phrase in radio communication, especially among truck drivers who use Citizens Band (CB) radio, many police departments have shifted to plain language communication, as ten-codes can vary in meaning across different jurisdictions. However, 10-4 has become a staple expression for saying “OK” in American pop culture and continues to be used in everyday conversations.

What are other similar codes, and what do they mean?

Ten-codes, also known as ten signals, are a collection of numeric codes representing specific phrases, such as:

  • 10-1: Bad radio reception
  • 10-2: Good radio reception
  • 10-3: Stop transmitting
  • 10-6: Stand by or busy
  • 10-7: Out of service
  • 10-8: In service
  • 10-9: Repeat message
  • 10-10: Negative
  • 10-17: En route
  • 10-20: Location
  • 10-21: Call by telephone
  • 10-23: Arrived at scene

While there are many more ten-codes, it’s important to note that they may vary between regions and agencies.

How do other words and phrases relate to radio communication?

In addition to ten-codes, radio communication often includes jargon and other phrases for clarity and brevity. Examples include:

  • “Roger that”: Understood or received
  • “Over”: Indicates the speaker is done talking and awaiting a response
  • “Repeat” or “Say again”: Request to repeat the last message
  • “Affirmative” or “Negative”: Yes or no
  • “Wilco”: Will comply with the given order or request

How have advancements in technology affected the use of 10-codes?

As radio communication technology has evolved, the need for standardized codes like 10-4 has decreased. Clearer transmissions and the widespread use of cell phones have made it easier to communicate effectively without the need for brevity codes. However, the use of ten-codes and related jargon remains prominent within specific communities, such as truck drivers and CB radio enthusiasts.

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