As A Boy Scout,

and I guess the same for Girl Guides,

 for woodcraft and sailing knots were taught,

 just a dozen or so to master,

 and you received your badge when the rest of the course was completed,

 but there are way more knots than the dozen or so we were taught, 

 in January of 2016, artist Windy Chien devoted herself to learning a new knot every day for a year, tying a total of 366 by December 31st (2016 was a leap year), this seems like a huge number of knots,

but is less than 10% of the knots she records in her book,

that contains 3,900 knots! the book is called The Ashley Book of Knots, which took its author nearly 11 years to compile, You can see a selection of Chien’s knots on her website, and view the entirety of the project on Instagram, and no I am not on commission! but what an Herculean task not only to remember how to tie each one but also making sure you have not knotted the same knot twice!