A second type of markup mentioned by Coombs, Renear, and DeRose is descriptive markup. Descriptive markup identifies the logical components of documents. While procedural markup specifies a particular procedure to be applied to a document component, descriptive markup indicates what the component is. None of these gives any indication of what procedures are to be applied to these components. But, if you know the elements in a document, then you can have processors to do whatever you want to them.
Descriptive markup liberates the document for multiple uses.
The fact that descriptive markup can be used in so many different ways is one of its important characteristics. It escapes the single use trap of procedural markup. Descriptive structural markup identifies document components and their logical relationship. Structural elements are components that you usually want to present visually in some distinct manner. Examples are chapter titles, paragraphs, block quotes, and the like.