What is a folio?
The word "folio" is familiar to many of us from books(especially historical and fantastic), on everyday conversations. It's no wonder that many people are thinking about what the word "folio" means, and where this word came from.
This word is calque from the German language. The German word "folio" was derived from the Latin folium, meaning "leaf". That is why folios were called old books, which were written (and subsequently printed) on folded paper sheets, which were then sewn together. Just in this sense, this word is used in most books.
And what is a folio in a more modern sense? Now more often than not, large and thick books are called impressive with their volume. On the benefits of reading such volumes, you can learn from the article Why books are needed.