One of the two techniques for communicating between parallel processes (the other being shared memory). A common use of message passing is for communication in a parallel computer. A process running on one processor may send a message to a process running on the same processor or another. The actual transmission of the message is usually handled by the run-time support of the language in which the processes are written, or by the operating system. Message passing scales better than shared memory, which is generally used in computers with relatively few processors. This is because the total communications bandwidth usually increases with the number of processors. A message passing system provides primitives for sending and receiving messages. These primitives may by either synchronous or asynchronous or both. A synchronous send will not complete (will not allow the sender to proceed) until the receiving process has received the message. This allows the sender to know whether the message was received successfully or not (like when you speak to someone on the telephone). An asynchronous send simply queues the message for transmission without waiting for it to be received (like posting a letter). A synchronous receive primitive will wait until there is a message to read whereas an asynchronous receive will return immediately, either with a message or to say that no message has arrived. Messages may be sent to a named process or to a named mailbox which may be readable by one or many processes. Transmission involves determining the location of the recipient and then choosing a route to reach that location. The message may be transmitted in one go or may be split into packets which are transmitted independently (e.g. using wormhole routing) and reassembled at the receiver. The message passing system must ensure that sufficient memory is available to buffer the message at its destination and at intermediate nodes. Messages may be typed or untyped at the programming language level. They may have a priority, allowing the receiver to read the highest priority messages first. Some message passing computers are the {MIT J-Machine (http://ai.mit.edu/projects/cva/cva_j_machine.html)}, the {Illinois Concert Project (http://www-csag.cs.uiuc.edu/projects/concert.html)} and transputer-based systems. Object-oriented programming uses message passing between objects as a metaphor for procedure call. (1994-11-11)

In computing, a private message, personal message, or direct message (abbreviated as PM or DM) refers to a private communication sent or received by a user of a private communication channel on any given platform. Unlike public posts, PMs are only viewable by the participants.

In cryptography, a message authentication code (MAC), sometimes known as a tag, is a short piece of information used for authenticating a message. In other words, to confirm that the message came from the stated sender (its authenticity) and has not been changed.

A variable- (also changeable-, electronic-, or dynamic-) message sign, often abbreviated VMS, CMS, or DMS, and in the UK known as a matrix sign,

The King's Christmas Message (also known as The Queen's Christmas Message in the reign of a female monarch, formally as His Majesty's Most Gracious Speech, and informally as the Royal Christmas Message) is a broadcast made by the sovereign of the United Kingdom and the other Commonwealth realms to the Commonwealth of Nations each Christmas. The tradition began in 1932 with a radio broadcast by King George V on the British Broadcasting Corporation's Empire Service.

MicroSoft Message Queue [Additional explanations: server] (Reference: MS)

Microsoft Message Queuing (MSMQ) is a message queue implementation developed by Microsoft and deployed in its Windows Server operating systems since Windows NT 4 and Windows 95. Windows Server 2016 and Windows 10 also includes this component.

The Message: The Bible in Contemporary Language is a version of the Bible by Eugene H. Peterson published in segments from 1993 to 2002.

WIP message is a work-in-progress message sent from a computer client to a computer server. It is used to update a server with the progress of an item during a manufacturing process.

In information security, message authentication or data origin authentication is a property that a message has not been modified while in transit (data integrity) and that the receiving party can verify the source of the message. Message authentication does not necessarily include the property of non-repudiation.