Origami is the art of folding figures, such as flowers and birds, from paper. But there is also geometric origami, resulting in more regular abstract forms. Since geometric origami can be very robust and esthetically pleasing, it has many applications in design, architecture and fashion. Henk van der Vorst, emeritus Professor of Numerical Analysis (UU), will discuss some folding techniques and their applications. He invites the audience to make some relatively simple geometric folds. Examples of his own folding will be on display in the exhibition IMAGINARY - Beauty and Power of Mathematics (to be seen from 1-18 November, DesignLab).