Introduction

Document preparation systems might be now the most commonly used computer systems, ranging from stand-alone text processing individual machines to highly sophisticated systems running on mainframe computers. All of those systems internally use a more or less formal system for representing documents. Document representation formalisms are very different according to their goals. Some of them define the interface with the printing device, they are oriented towards a precise geometric description of the contents of each page in a document. Others are used internally in systems as a memory representation. Yet others have to be learned by users ; they are symbolic languages used to control document processing.

The trouble is that there are today nearly as many representation formalisms as document preparation systems. This makes it nearly impossible, first to interchange documents among heterogeneous systems, second to have standard programming interfaces for developping systems. Standardization organizations and large companies are now trying to establish standards in the field in order to stop proliferation of formalisms and facilitate document interchange.

This paper focuses in the last sections on three document representation formalisms often called ‘revisable formats’, namely SGML [SGML], ODA [ODA], and Interscript [Ayers & al.], [Joloboff & al.]. In order to better understand what is a revisable format, the paper starts with a look at the evolution of the architecture of document preparation systems.