Do you know that Tsuru (paper crane, is a design that is considered to be the most classic of all Japanese origami? And that in Japanese culture, it is believed that its wings carry souls up to paradise? Also, some stories believe you are granted happiness and eternal good luck if you fold tsurus. (Source_ Wikipedia).
That's why I love to leave them around for people to find!
Below you'll find a step-by-step how to fold a tsuru.
(affiliate link for your convenience)
How to fold a crane (Tsuru) origami
(chart by Andrew Hudson)