In an integration solution built on the publish-and-subscribe model, applications publish and subscribe to documents. Documents are objects that webMethods components use to encapsulate and exchange data. A document represents the body of data that a resource passes to webMethods components. Often it represents a business event such as placing an order (purchase order document), shipping goods (shipping notice), or adding a new employee (new employee record).

Each published document includes an envelope. The envelope is much like a header in an email message. The envelope records information such as the sender’s address, the time the document was sent, sequence numbers, and other useful information for routing and control. It contains information about the document and its transit through your webMethods system.