Securing loose printed, folded, and nested pages with stitches or staples down the middle of the fold (the spine) is known as saddle-stitched binding. The sheaf of papers or signature may be stitched with thread or staples. The name comes from the device or saddle on which the folded signatures are placed for stitching — with the saddle in the fold.
The cheapest, fastest, most popular option.
Saddle stitch printing or “booklet” printing is a very common form of printing where the material is formed into a small book by folding the pages with staples down the spine or middle of the book. Saddle stitch paper is usually either 8.5″ x 11″ or 5.5″ x 8.5″ and usually the total page length of each booklet must be under 64 pages.
Saddle-stitching or saddle-stapling or “booklet making” is common for small booklets, calendars, pocket-size address books, and some magazines . Binding with saddle-stitching creates booklets that can be opened up flat. The number of pages that can be bound using saddle-stitching is limited by the bulk of the papers. The larger the number of pages, the greater the amount of creep that occurs; inner pages that extend or creep further out than the outer pages when folded. These books can lie flat and have no spine on which to print a title.