In this article, the author investigates effective teaching and learning of geometrical concepts using dynamic geometry software (DGS). Based from her students' reactions to her project, the author found that her students' understanding of the concepts was better than if they had learned geometry through paper-based tasks. However, mixing computer work with paper-based task is probably the best way to ensure the students can access the mathematics and enhance their understanding further. The author suggests that when using DGS, teachers must consider two elements in particular: (1) the medium of computer; and (2) computer-generated geometry versus paper geometry. (Contains 5 figures and 3 notes.)