The purpose of this Technical Specification is to define the syntax rules for a data stream for the submission of printing data to a Hybrid Mail operator or between Hybrid Mail operators. The Technical Specification defines an XML Schema Definition (XSD) describing the data stream.

The description is based upon the XML (eXtended Mark-up Language) definition of rules and semantics for defining an XSD. The purpose of this is to offer a generalised syntax description that can provide seamless integration with a number of existing applications generating data that is liable to be forwarded to or from a Hybrid Mail operator.

The use of an XSD will ensure that the documents confirm to the standard defined and that the output has the correct syntax. Software manufacturers can use an XSD to program applications that will produce “correct” outputs.

This Technical Specification defines the syntax for creating a data stream that will eventually be converted into a deliverable. The overall object (a batch) can be divided into one or more objects that again can be divided into objects. The hierarchy includes bundles that contain a common part and letters. Each object has a number of characteristics attached to it.

This diagram shows the structure of a HML (Hybrid Mail Language) document: each letter is self-contained (contains all the necessary information to be delivered on a certain destination).

Each letter can have one contact. Each contact can have multiple alternatives for delivery.

This Technical Specification does not define the specific services offered by local operators (Hybrid Mail operators).

This Technical Specification does not define the communication method used. It does only define the format of Hybrid Mail as such.