RFC 1003 (rfc1003) - Page 2 of 7
Issues in defining an equations representation standard
Alternative Format: Original Text Document
RFC 1003 March 1987 include equations in messages. A glance through any scientific journal will demonstrate the importance of equations in scientific communication. Indeed, papers in some fields seem to contain more mathematics than English. It is hard to imagine that when people in these fields are connected into an electronic mail community they will be satisfied with a mail system which doesn't allow equations. Indeed, with the advent of the NSF's Experimental Research in Electronic Submission (EXPRESS) project, scientists will begin submitting manuscripts and project proposals directly through electronic mail and the ability to handle equations will be essential. Currently, there exists no standard for the representation of equations. In fact, there is not even agreement on what it is that ought to be represented. Users of particular equation systems (such as LaTex or EQN) sometimes advocate just including source files of that system in messages, but this may not be a good long-term solution. With the new NSF community coming on line in the near future, I feel the time is now right to try to define a standard which will meet the present and future needs of the user community. Such a standard should allow the interchange of equations via electronic mail as well as be compatible with as many existing systems as possible. It should be as general as possible, but still efficiently represent those aspects of equations which are most commonly used. One point to be kept in mind is that most equations typesetting is currently being done by secretaries and professional typesetters who do not know what the equations mean, only what they look like. Although this is mainly a user interface consideration, any proposed standard must not require the user to understand an equation in order to type it in. We are not interested here in representing mathematics, only displayed equations. In this memo, I will try to raise issues that will need to be considered in defining such a standard and to get a handle on what it is that needs to be represented. Hopefully, this will form the basis of a discussion leading eventually to a definition. Before examining what it is that could be or should be represented in the standard, we will first review the characteristics of some existing systems. 2. Existing Systems There currently exist many incompatible systems which can handle equations to a certain extent. Most of these are extensions to text formatting systems to allow the inclusion of equations. As such, general representation and standards considerations were not a major concern when these systems were initially designed. We will examine the three main types of systems: Directive systems, Symbolic Language systems, and Full Display systems. Katz
