Chapters Start on Recto Pages
Books can have blank pages too. The vast majority of books follow the industry standard of chapter openers starting on a Recto, or right-hand (odd) page. Often, the prior chapter ends on an odd-numbered page. When this happens, it is customary to make the back of that page blank, to allow the next chapter to start on the correct page. This is also true for many front matter pages like dedications and quotations.
Books have Gutter Margins
Books have bindings in the center to hold all of the pages together. These bindings cause the pages to roll inward toward the center in what is called a gutter. Extra page spacing, or gutter margins, are required on the inside edges of the page to account for the gutter. Even pages will have larger margins on the right side, and odd pages will have larger margins on the left side to allow the page to appear centered when bound in book form.