I love Z-library, it's obvious that once we've found a means of transmitting books as "code/software/bits", the concept of copyright was changed forever, the catalog available in Z-library is superb, and the site is easy to navigate.

What I see talked way less is that the quality of new books, in light of this, is very bad. Most books out there that were published in the 21st century serve as business cards. Commoditizing the complement, they call it.