I gave it up for lint

What is lint made of? As in, the stuff in the bottoms of your jeans pockets after you take them out of the dryer.

In addition to its ingredients, how does it become so solid and felt-y?

“In much wisdom is much grief; and he that increaseth knowledge increaseth sorrow.” - Ecclesiastes 1:18

Lint is composed mainly of short fibers from the cloth making up your clothes. It gets “felted” from the combination of moisture and compression.

“To do her justice, I can’t see that she could have found anything nastier to say if she’d thought it out with both hands for a fortnight.”
Dorothy L. Sayers
Busman’s Honeymoon

I take the dryer lint and leave it in the woods. I imagine some little critter might want a soft lining for their nest. OK, so I’m a bit tetched in the head…