Intentionally blank pages, or vacat pages, are common in printed works to separate content or signal the end of a section. These pages are a result of printing conventions where chapters typically start on odd-numbered pages. They are also used to prevent cheating in standardized tests by separating sections. In sheet music, blank pages minimize page turns for performers. Interestingly, classified documents in the US military use intentionally blank pages for organized page checks. Some books contain entirely blank pages as a novelty. Authors like Andy Griffiths and Demetri Martin have creatively incorporated intentionally blank pages into their works.
https://en.wikipedia.org/wiki/Intentionally_blank_page