What is a message?
A message is a communication asset that transmits or exchanges information from a sender to the receiver through channels.
One message can also be defined as an event or command and can be consumed by multiple independent receivers. The sender encodes a payload of data (serialized into a suitable format, such as JSON, XML, binary, or others) that requires processing by the receiver. Additionally, the message may include metadata, which is information that describes the message itself. This metadata is commonly referred to as headers or properties.
The diagram above illustrates how a sender application transmits a message through a channel to a receiver application, demonstrating the basic flow of message-based communication.
Messages vs Events
A message conveys information between applications, while an event is a message that provides details of something that has already occurred. A crucial aspect to note is that depending on the type of information a message carries, it can either be an event, query, or command. Check the diagram below.
Summing up, events are messages, but not all messages are events.
