Mindmaps might be considered to be shorthand for all the material covered in the text books and in class. They are a pretty good summary of all you need to know to get excellent exam results. They are visual in nature and therefore are easy to remember and recall for the vast majority of students. They focus on key material you need to know and act as a prompt for further information you will have learned in class or at home. If you have left it too late to start Mind Mapping you can always access the ones I have created online. There are free samples in 8 different subjects so that you can check if they work for you.