Twill is a type of fabric woven with a pattern of diagonal parallel ribs.

It is made by passing the weft thread over one or more warp threads
and then under two or more warp threads and so on, with a "step" or
offset between rows to create the characteristic diagonal pattern.
Because of this structure, twills generally drape well.

Are the fabrics warp-faced?

Are the fabrics even-sided?