What Is Communication?

Learning Objectives

Identify the various elements of the communication process.

If you’ve ever struggled to express a thought, you know that we experience, feel, and think about far more than we will ever be able to communicate. Our psyche is filled with abstract ideas and feelings. Since we cannot read each other’s minds, in order to interact with others, we use symbols to represent the abstract realm in our own head. For example, by stating “table” you are not actually making a table appear. Rather you are using a symbol—a word—to represent it. Similarly, a smile might represent the feeling of happiness, but it is not the actual feeling itself.

Communication (from Latin communicare, meaning “to share”) is the act of conveying meanings from one entity or group to another through the use of mutually understood signs, symbols, and semiotic rules. (Wikipedia) Or, more concisely, “the symbolic process of sharing meanings.” [1]

Because communication—even just saying what’s on your mind—is so complicated, several models of this process have been developed over the years.

The Linear Model of Communication

One of the founding documents of modern information theory was A Mathematical Theory of Communication, published in 1948 by the mathematician Claude Shannon. In this article, Shannon proposed a model of communication that moved linearly from the source to the destination via some form of transmission.

The information source passes a message to the transmitter, then a signal for the transmitter is passed to the receiver. As that signal is being passes, a noise source can affect the signal, which then becomes the received signal that is passed to the receiver. The receiver passes the message to the destination.

Importantly, Shannon’s model wasn’t concerned at all with the intended meaning of the message (what he called its “semantic aspects”). He was far more interested in whether the signal could get through at all. The fact that Shannon’s article appeared in Bell Labs’ Bell System Technical Journal gives some indication of the engineering problem he was trying to solve: Shannon’s model is concerned with the technologies of the telegraph, the telephone, and the radio. With signals traveling through crowded telegraph or telephone lines, or across the busy airwaves, a lot can go wrong. (You know this if you’ve ever picked up two overlapping radio stations while driving). This disruption of the transmitted signal is called noise in Shannon’s model. [2] As we’ll see, Shannon’s model had an enormous influence on later understandings of communication, from the distinction between sender, channel, noise, and receiver to the emphasis on the technological media of communication.

Shannon was interested in the technological processes that would allow a signal to get through despite the inevitable noise in the system. But what if the signal gets through, but isn’t understood properly at the receiving end?


Alfred, Lord Tennyson’s famous poem “The Charge of the Light Brigade” (1854) tells the story of a doomed charge by the British light cavalry during the Crimean war (1853–1856). In Tennyson’s poem, we read that the light brigade had been told to “Charge for the guns,” and did so, with catastrophic results:

Charge of the Light Brigade by Richard Caton Woodville Jr., 1894

“Someone had blundered.” Charge of the Light Brigade by Richard Caton Woodville Jr., 1894

Not though the soldier knew
Someone had blundered.
Theirs not to make reply,
Theirs not to reason why,
Theirs but to do and die.
Into the valley of Death
Rode the six hundred.

What was the “blunder” the poet refers to here? The cavalry was attacking the wrong guns! When the messenger carrying the order was asked which guns they should attack, he evidently made a vague gesture, perhaps of uncertainty, sweeping his arm across the battlefield. Instead of the relatively minor side action intended by the order, the Light Brigade launched a courageous but disastrous frontal attack on well-entrenched Russian artillery.

As the story of the Light Brigade demonstrates, even a simple gesture holds the possibility of misinterpretation. How can we account for the fact that the intended meaning of a communication does not always match up to the way the message is interpreted?

Encoding and Decoding

Stuart Hall

Stuart Hall (1932–2014)

In the case of miscommunication, we see a discrepancy between the process of encoding, or producing a meaningful message for an audience, and decoding, the process of interpreting the message.

Stuart Hall, a Jamaican-born British cultural studies theorist, proposed a model of communication that explored the differences between the intended meaning and the interpreted meaning of a message. In his 1973 essay “Encoding and Decoding in the Television Discourse,” Hall describes the many factors that influence the encoding and decoding process. Hall is particularly interested in the cultural, political, and economic environments within which messages are produced and received. Hall’s essay reminds us that the messages encoded in a television show, a political advertisement, or the nightly news will be interpreted very differently depending on the viewer’s background, circumstances, or beliefs. Where one viewer might see an affirmation of their worldview, another might reject the message as false or irrelevant. Hall’s model reminds us that meaning is created not just in the moment of encoding a message, but also in the way that message is decoded.[3]

Transactional Model of Communication

In thinking about two-way communication, many contemporary communication theorists combine elements of the linear model (e.g., the distinctions between sender, channel, noise, and receiver) with accounts, like Hall’s, of the way meaning is created at multiple sites within the communication process. One influential model of two-way communication is Barnlund’s transactional model of communication (1970)where meaning is co-created simultaneously by both parties.[4]

  • Communicators simultaneously encode and decode symbols with each other to create meaning.  Not all communications are intentional, as anyone who has sent or received a “reply all” email can attest. We may also be unaware that we are a communicator. Almost everyone sends nonverbal symbols without realizing it. As long as someone else is decoding the symbols you encode or you are decoding theirs, you become a communicator.
  • Message is the meaning created from the verbal and nonverbal content of the communication. Sometimes the verbal and nonverbal components of a message contradict. As an example, Susan curtly says, “I’m fine” with her arms crossed while evading eye contact. In these cases, more weight is usually given to the nonverbal component of the message to determine meaning.
  • Feedback is the response to the message one communicator sends to the other. However, since both communicators send feedback to each other at the same time, feedback also becomes a message.
  • Channel is the mode through which a message is communicated. Whether one communicates in person, via text, or over video chat can influence the clarity of the communication. A chosen channel can limit or expand the range of symbols available to a communicator. Consider the benefits and drawbacks of communicating through each channel.
In person Radio TV/Internet broadcast Text
Phone Email Video chat Social Media
  • Interference is any internal or external noise that blocks a communicator from decoding the message.
    • Internal noise includes anything drawing attention away from the message. Examples include daydreaming, pain, or thinking about something else.
    • External noise is a physical barrier to hearing or seeing the message. Examples include a noisy environment, distance, or technology failure.
  • Context refers to the environment surrounding the communicators and the communication event. It includes the relationship between the communicators, the purpose for the communication, the greater scheme of current events, and the physical environment as well as each communicator’s psychological state. Context helps communicators predict and understand the interpretation of a message in a given interaction.
There are two people talking to one another and they are labeled “Communicators.” Physical and psychological context, cultural context, relational context, and social context all play a part in the co-creation of meaning, which happens between the two communicators.

Thought experiment

Think of a recent miscommunication you’ve experienced. Analyze the event using the components of the transactional communication model to identify where the miscommunication may have occurred.

Try It

  1. Galvin, Kathleen M., and Charles A. Wilkinson. “The Communication Process: Impersonal and Interpersonal.” Making Connections: Readings in Relational Communication, by Kathleen M. Galvin, Oxford University Press, 2011, p. 5.
  2. Shannon, Claude. "A Mathematical Theory of Communication." The Bell System Technical Journal, Vol. 27, pp. 379–423, 623–656, July, October, 1948. http://people.math.harvard.edu/~ctm/home/text/others/shannon/entropy/entropy.pdf
  3. Hall, Stuart. "Encoding and Decoding in the Television Discourse." Essential Essays, Volume 1: Foundations of Cultural Studies. Duke University Press, 2018.
  4. Barnlund, Dean. "A Transactional Model of Communication" (1970). Communication Theory, edited by C. D. Mortensen, Routledge, 2017, pp. 47–58.