What is a Rubric:
In the non-academic arena, a rubric is usually referred to side notes in prayers.  These side notes, usually in red ink, hence the root of the word in latin meaning red or red ochre, were used to tell prayers what to do.  Later in academia, red ink was used in grading student papers to hint them of their errors.  Teachers begun to standardize these notes.  For example, some would use "SP" to mark spelling errors.