Introduction to SGML concepts

The paper provides an introduction to the concepts of SGML. Text processing systems typically require additional information to be interspersed among the natural text of the document being processed. This additional information, called `markup´, serves two purposes: separating the logical elements of the document, and specifying the processing instructions to be performed on those elements. The three types of markup: procedural, generalized and descriptive, are all described. The benefits and use of SGML for descriptive markup are also outlined