In the 1980's, document preparation systems turned to a more logical viewpoint of a document by considering a document's logical structure.

Brian Reid developed a document preparation system at CMU called Scribe which used a high-level language to describe a document in logical terms rather than as a function of its presentation.

Goldfarb , at IBM, was motivated by Reid, and developed the concept of declarative markup:

" ... it does not restrict documents to a single application, formatting style, or processing system. ... Markup should describe structure, ... rather than specifying processing to be performed on it ... "

This is the object-oriented viewpoint and, in the programming language field, led to what are called declarative languages. These languages specify what to do, not how to do it.

Both the object-oriented programming language development and the declarative markup concepts were continued at Xerox Parc.

Thus, programming languages separate what (is to be done) from how (it is done), while formatting languages separate what (the structure is) from how (the document is to look).

During this time, laser printers became better and dropped in price to the point where many people could afford to buy them.

In the middle-to-late 80's the concept of a structured document evolved. In this model, there are three representations of the document: the logical document, the physical document and the display document.

And now we're in the 1990's..., heading toward the 21st century.

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