ToolTalk messages are simple structures that contain fields for address, subject, and delivery information. To send a ToolTalk message, an application obtains an empty message, fills in the message attributes, and sends the message. The sending application needs to provide the following information:
Is the message a notice or a request (that is, should the recipient respond to the message)?
What interest does the recipient share with the sender? (For example, is the recipient running in a specific user session or interested in a specific file?)
To narrow the focus of the message delivery, the sending application can provide more information in the message.