An IETM is an interactive electronic version of a technical document. It contains all the information a technician needs to perform his or her function: procedures, parts information and theory information. The information can be loaded onto a lightweight, portable computer that the technician can use where needed. There are 6 recognised classes of IETM, ranging from non-indexed page images (scanned) to an integrated database information system.
- Class 0: Non-Electronically-Indexed Page Images (Not an ETM) - Systems of digital page images that are intended for electronic archival filing or Print-on-Demand. Pages can be viewed in an electronic display but have no index for navigation through the document for the purpose of online usage.
- Class 1: Electronically Indexed Page Images - Systems of digital page images intended for full-page display. Automatic intelligent indexing allows navigation to the page images for user access. These systems can be used in a library or reference setting for reading and research use. They can be printed directly.
- Class 2: Electronic Scrolling Documents - Systems for interactive display of ASCII-based documents using intelligent indexing and Hypertext tags inserted into a tagged document file. This type of document is generally the result of a simple conversion from a page-oriented document with the addition of Hypertext tags. This allows navigation of the document by the user, however, content driven NEXT function and author inserted navigation aids are very limited, if any.
- Class 3: Linear Structured IETPs - Interactive display of technical information which is in SGML format to the maximum extent possible and using a Hypertext presentation system for display. Rather than being based on a hierarchically based database, it is based on a linear SGML document file. Navigation is based on content driven logical NEXT function and author developed constructs employing prompted dialog boxes.
- Class 4: Hierarchically Structured IETPs - System for interactive electronic display of technical information specifically authored into and maintained in a relational or object-oriented hierarchical database with no redundancy of data. The data is then packaged as a run-time database for interactive presentation (IETP).
- Class 5: Integrated Database IETIS - Integrated electronic technical information system for interactive presentation of Class 4 IETPs integrated in with data for other processes and systems for information display and user-applications such as computer aided training or fault diagnostics.
