In many papers that are Brailled for students, these drawings are left out and the student is instructed to ask the teacher to explain them. In dotsplus these illustrations are incorporated directly into the document. The illustration is then printed out in raised mode along with the rest of the document. There are, however, a few things that must happen before these two systems can be widely used. This leads us to a final discussion of the accessibility of documents.
Documents come in a hierarchy of accessibility.
All printer languages are designed to tell the printer only where on the page to put a character and what font to use when printing it. To a page description language, a fraction is just one character over another separated by a line. Page description languages are inherently visual in nature and contain no information about what they are printing except to someone who can see the page. Only slightly below the printer languages in accessibility is a piece of paper or its electronic equivalent, the bitmap. To make these accessible requires sophisticated optical character recognition software and as yet, there is no optical character recognition software that recognizes mathematical text.