Index cards are very beneficial in summarising the key points and can easily be rearranged in the content of the essay. They are also useful to find the most logical grouping and order of points.Once the order is chosen, simply number the cards can fix the order of the essay plan It is very convenient to take notes on index cards because it gives you the flexibility the order of your notes and group them together easily. It is also a great way to organize research, with group and color-code your can create an outline easily by adding supporting information.