Folds

when an artist draws them well you don't even notice them; you only notice when they're drawn poorly. - Mark Kennedy

Milt Kahl

Folds are like hair, in that they reveal alot about the artist drawing them.  They are a window into how an artist sees and edits the world around them.  They are also a window into The artist's knowledge and purpose.

Folds show:

Stretch and squash

Gravity

knowledge and thought into costume

anatomical construction

3D forms

Balance of detail

Streamlining

There is also a lot of personality in folds.  Like Hair, folds are somewhat abstract and  every artist draws them just slightly differently and whatever the subject matter is often a clue to who drew it.
They are also a type of artist signature.

There are a few different types of folds.  go HERE for a breakdown of each kind of fold and how and where they are found on the figure

and HERE for more pages from the famous Artists cartoon course - Folds and drapery

and HERE for the Pintrest collection of knowledge on folds

Here are some more examples of Designing folds

kim jung

Sam Bosma

Scottie Young

Nico Marlet

 Secret of Kells

Giannis