Grading guides are an advanced grading method used in Moodle Assignments. They allow the instructor to design a set of criteria that are used as a form when grading student submissions allowing the instructor to leave a comment a score for each criterion. The form totals the score and calculates the final grade for the assignment.
While similar to a Rubric, a Grading guide does not allow you to rank each criterion according to multiple levels and instead, has a single comment box and one numeric score. Grading guides also allow the instructor to create a comment bank to use when grading.