A message is a discrete unit of communication intended by the source for consumption by some recipient or group of recipients. A message may be delivered by various means, including courier, telegraphy, carrier pigeon and electronic bus. A message can be the content of a broadcast. An interactive exchange of messages forms a conversation.^[1]

One example of a message is a press release, which may vary from a brief report or statement released by a public agency to commercial publicity material.

History

Roles in human communication

In communication between humans, messages can be verbal or nonverbal:

• A verbal message is an exchange of information using words. Examples include face-to-face communication, telephone calls, voicemails, emails, etc.
• A nonverbal message is communicated through actions or behaviors rather than words, such as conscious or unconscious body language.

The phrase "send a message" or "sending a message" is also used for actions taken by a party to convey that party's attitude towards a certain thing. For example, a government that executes people who commit acts of treason is sending a message that treason will not be tolerated.^[2] Conversely, a party that appears through its actions to endorse something that it opposes can be said to be "sending the wrong message",^[2] while one which appears to simultaneously endorse contradictory things can be said to be sending "mixed messages".^[3]

In computer science

There are two main senses of the word "message" in computing: messages between the human users of computer systems that are delivered by those computer systems, and messages passed between programs or between components of a single program, for their purposes.

• Instant messaging and emails are examples of computer software designed for delivering human-readable messages in formatted or unformatted text, from one person to another.
• Message passing is a form of communication used in concurrent and parallel computing, object-oriented programming, and channel communicates, where communication is made by sending messages to recipients. In a related use of this sense of a message, in object-oriented programming language such as main library ["msg" box]Smalltalk or Java, a message is sent to an object, specifying a request for action.

Safety and privacy concerns

Safety and privacy concerns have been expressed in the computer science industry regarding messages. There have been cases where instant messaging apps were found to present a risk of spyware infection.^[4] Text messaging is one of the larger causes of distracted driving, and the act of texting and driving has been made illegal in many states as a result.^[5]