Mathematician and part-time calligrapher Andrew Stacey has assembled a beautiful guide to mathematical calligraphy, from the way mathematicians use notation to how different types of symbols can be written using calligraphy techniques. So you can sign all your Christmas cards with maths notation, and keep them looking pretty at the same time!

This is part of the Aperiodical Advent Calendar. We’ll be posting a new surprise for you each morning until Christmas!