A miniature book is a very small book. Standards for what may be termed a miniature rather than just a small book have changed through time. Today, most collectors consider a book to be miniature only if it is 3 inches or smaller in height, width, and thickness, particularly in the United States. Many collectors consider nineteenth-century and earlier books of 4 inches to fit in the category of miniatures. Book from 3-4 inches in all dimensions are termed macrominiature books. Books less than 1 inch in all dimensions are called microminiature books. Books less than 1/4 inch in all dimensions are known as ultra-microminiature books.
Miniature books stretch back far in history; many collections contain cuneiform tablets stretching back thousands of years, and exquisite medieval Books of Hours. Printers began testing the limits of size not long after the technology of printing began, and around 200 miniature books were printed in the sixteenth century. Exquisite specimens from the 17th century abound. In the 19th century, technological innovations in printing enabled the creation of smaller and smaller type. Fine and popular additions alike grew in number throughout the 19th century in what was considered the golden age for miniature books. While some miniature books are objects of high craft, bound in fine Moroccan leather, with gilt decoration and excellent examples of woodcuts, etchings, and watermarks, others are cheap, disposable, sometimes highly functional items not expected to survive. Today, miniature books are produced both as fine works of craft and as commercial products found in chain bookstores.
Miniature books were produced for personal convenience. Miniature books could be easily be carried in the pocket of a waistcoat or a woman's reticule. Victorian women used miniature etiquette books to subtly ascertain information on polite behavior in society. Along with etiquette books, Victorian women that had copies of The Little Flirt learned to attract men by using items already in their possession, such as, gloves, handkerchiefs, a fan and parasol. In 1922, miniature books regained popularity when 200 postage stamp sized books were created to be displayed in the miniature library of Queen Mary's miniature doll house. Princess Marie Louise, a relative of Queen Mary also requested that living authors contribute to the existing dollhouse library. Following in Queen Mary footsteps, many miniature book collectors begin collecting miniatures for their dollhouse libraries. A miniature book has even been to the moon. In 1969, Astronaut “Buzz” Aldrin had a miniature book in his possession during a flight to the moon. It was an autobiography of Robert Hutchings Goddard, who invented the first liquid-propellant rocket that make space flight possible.
Some popular types of miniature books from various periods include Bibles, encyclopedias, dictionaries, bilingual dictionaries, short stories, verse, famous speeches, political propaganda, travel guides, almanacs, children's stories, and the miniaturization of well-known books such as The Compleat Angler, The Art of War, and Sherlock Holmes stories. The appeal of miniature books was holding the works of prominent writers, such as William Shakespeare in the person's hands.
Abraham Lincoln, Proclamation of Emancipation (Boston : John Murray Forbes, 1863). This miniature edition was the first of this text. It is estimated that a million copies were distributed to Union troops.
Many books have claim to the title of smallest book in the world at the time of their publication. The title can apply to a variety of accomplishments: smallest overall size, smallest book with movable type, smallest printed book, smallest book legible to the naked eye, and so on.
750: Hyakumantō Darani or ‘One Million Pagoda Dharani.' Also one of the earliest known printed texts, these 2-3/8" tall Buddhist charms were printed, rolled into a scroll, placed in miniature white pagodas, and distributed to Buddhist temples. A million were printed at the command of Japanese Empress Shōtoku.
1674: Bloem-Hofje (Amsterdam: Benedict Schmidt, 1674). For more than two centuries, this remained the smallest book printed with moveable type.
1878: Dante, Divina Commedia (Milan: Gnocchi, 1878). 500 pages. 5 cm x 3.5 cm. Typeset and printed by the Salmin Brothers of Padua.
1897: Galileo Galilei. Galileo a Madama Cristina di Lorena (Padua: dei Fratelli Salmin, 1897). 150 pages. This remains to this day the smallest book set from movable type.
1900: Edward Fitzgerald, trans. The Rubaiyat of Omar Khayyam (Cleveland: Charles H. Meigs, 1900).
1932: The Rose Garden of Omar Khayyam.
1985: Old King Cole (Paisley: Gleniffer Press, 1985). Height: 0.9 mm. For 20 years this was the "smallest book in the world printed using offset lithography".
2001: New Testament (King James version) Cambridge: M.I.T, (2001). 5 x 5 mm.
2002: Anton Chekhov, Chameleon (Omsk, Siberia: Anatoly Konenko, 1996) 0.9 mm x 0.9 mm.
2006: ABC books in Russian and Roman characters (Omsk, Siberia: Anatoly Konenko, 1996). 0.8 mm x 0.8 mm
2007: Teeny Ted from Turnip Town (category: world's smallest reproduction of a printed book. Single sheet, not codex format.) 0.07 x 0.10 mm
2016: Vladimir Aniskin, [Untitled] (Russia: Vladimir Aniskin, 2016). "The micro-book consists of several pages, each measuring only very tiny fractions of a millimeter: the precise size of the pages is 70 by 90 micrometers or 0.07 by 0.09 millimeters — too small to be read by the naked human eye. Made by gluing white paint to extremely thin film, the pages are hung from a tiny ring binder that allows them to be turned. The whole construction rests on a horizontal sliver of a poppy seed."
In 2007, archaeologists found a miniature Bible (Glasgow: David Bryce & Son, 1901) tucked into a child's boot hidden in a chimney cavity in an English cottage in Ewerby, Lincolnshire. Shoes were placed in such locations as early as the fourteenth-century as anti-witchcraft devices known as "spirit traps."
The creation of a miniature book requires exceptional skill in all aspects of book production, because elements such as bindings, pages, and type, illustrations, and subject matter all need to be approached with a new set of problems in mind. For instance, the pages of a miniature book do not fall open as do those of larger books, because the pages are not heavy enough. Bindings require exceptionally thin materials, and creating type that is readable and beautiful requires great skill. Many printers have created miniature books to test their own technical limits or to show off their skill. Many books have claimed the sought-after title of "smallest book in the world," which is now held by experiments in nanoprinting.
Mystical Places Press, Wenatchee, WA
Good Book Press, Santa Cruz, California
Dawson's Book Shop, Los Angeles, CA
The Gleniffer Press
Gloria Stuart, the film actress, published numerous miniature books as collaborations with significant printers
Plum Park Press
The Smallest Books in the World, Peru
Miniboox German publisher of miniature books 
Achille St. Onge
Букос(Bookos), russian publisher specializing in miniature craft books, Russia
HarperCollins, Collins Gem Books division.
Oxford University Press published many miniature religious books and children's books in the late 19th and early 20th century.
Running Press, known for miniature books marketed as impulse buys in bookstore checkout lines.
Sanrio, known for tiny blank books in its Hello Kitty, Little Twin Stars, and other lines starting in the late 1960s and early 1970s.
Sangorski & Sutcliffe
Prominent historical figures who collected miniature books include President Franklin D. Roosevelt and retailer Stanley Marcus.