Once you have completed a module, your work will be marked using a letter grade, usually A, B, C, D or F. More details of the letter grades for each grading system are listed below. These letter are each assigned a numeric value such that an average can be taken. In the GPA 4.0 system, an A grade receives 4 points, a B=3, a C=2, a D=1, and an F=0.
Credits are uses to balance the relative amount of effort required by your modules. Each module is assigned a certain number of "credits", depending on the content of the course. These credits are multiplied by your letter grades.