A book is a set of written, printed, illustrated, or blank sheets, made of ink, paper, parchment, or other materials, usually fastened together to hinge at one side. A single sheet within a book is called a leaf, and each side of a leaf is called a page. A book produced in electronic format is known as an electronic book (e-book).

Books may also refer to works of literature, or a main division of such a work. In library and information science, a book is called a monograph, to distinguish it from serial periodicals such as magazines, journals or newspapers. The body of all written works including books is literature. In novels and sometimes other types of books (for example, biographies), a book may be divided into several large sections, also called books (Book 1, Book 2, Book 3, and so on). A lover of books is usually referred to as a bibliophile or, more informally, a bookworm.

A store where books are bought and sold is a bookstore or bookshop. Books can also be borrowed from libraries. In 2010, Google estimated that since the invention of printing, approximately 130,000,000 unique titles had been published.

The domestic cat (Felis catus or Felis silvestris catus, informally Felis domesticus) is a small, usually furry, domesticated, carnivorous mammal. It is often called the housecat when kept as an indoor pet, or simply the cat when there is no need to distinguish it from other felids and felines. Cats are valued by humans for companionship and ability to hunt vermin and household pests. They are primarily nocturnal.

Cats are similar in anatomy to the other felids, with strong, flexible bodies, quick reflexes, sharp retractable claws, and teeth adapted to killing small prey. As crepuscular predators, cats use their acute hearing and ability to see in near darkness to locate prey. Not only can cats hear sounds too faint for human ears, they can also hear sounds higher in frequency than humans can perceive. This is because the usual prey of cats (particularly rodents such as mice) make high frequency noises, so the hearing of the cat has evolved to pinpoint these faint high-pitched sounds. Cats also have a much better sense of smell than humans.

Theodor Seuss Geisel ( /ˈɡaɪzəl/; March 2, 1904 – September 24, 1991) was an American writer, poet, and cartoonist most widely known for his children's books written under the pen names Dr. Seuss, Theo LeSieg and, in one case, Rosetta Stone.

He published 46 children's books, which were often characterized by imaginative characters, rhyme, and frequent use of anapestic meter. His most celebrated books include the bestselling Green Eggs and Ham, The Cat in the Hat, One Fish Two Fish Red Fish Blue Fish, Horton Hatches the Egg, Horton Hears a Who!, and How the Grinch Stole Christmas!. Numerous adaptations of his work have been created, including 11 television specials, four feature films, a Broadway musical and four television series. He won the Lewis Carroll Shelf Award in 1958 for Horton Hatches the Egg and again in 1961 for And to Think That I Saw It on Mulberry Street.

Geisel also worked as an illustrator for advertising campaigns, most notably for Flit and Standard Oil, and as a political cartoonist for PM, a New York City newspaper. During World War II, he worked in an animation department of the United States Army, where he wrote Design for Death, a film that later won the 1947 Academy Award for Documentary Feature.

Justin Drew Bieber ( /ˈbiːbər/ BEE-bər, born March 1, 1994) is a Canadian Pop/R&B singer-songwriter, musician, and actor. Bieber was discovered in 2008 by Scooter Braun, who came across Bieber's videos on YouTube and later became his manager. Braun arranged for him to meet with Usher in Atlanta, Georgia, and Bieber was soon signed to Raymond Braun Media Group (RBMG), a joint venture between Braun and Usher, and then to a recording contract with Island Records offered by L.A. Reid. Bieber's debut single, "One Time", was released in 2009 and peaked in the top twenty in Canada and charted in the top thirty in several international markets. His debut album, the seven-track EP My World, followed in November 2009, and was soon certified platinum in the United States. He became the first artist to have seven songs from a debut album chart on the Billboard Hot 100.

Kurt Vonnegut, Jr. ( /ˈvɒnɨɡət/; November 11, 1922 – April 11, 2007) was a 20th century American writer. His works such as Cat's Cradle (1963), Slaughterhouse-Five (1969), and Breakfast of Champions (1973) blend satire, gallows humor, and science fiction. As a citizen he was a lifelong supporter of the American Civil Liberties Union and a critical leftist intellectual. He was known for his humanist beliefs and was honorary president of the American Humanist Association.

Kurt Vonnegut, Jr. was born in Indianapolis, Indiana, to third-generation German-American parents, Kurt Vonnegut, Sr. and Edith Lieber. Both his father and his grandfather Bernard Vonnegut attended Massachusetts Institute of Technology and were architects in the Indianapolis firm of Vonnegut & Bohn. His great-grandfather Clemens Vonnegut, Sr. was the founder of the Vonnegut Hardware Company, an Indianapolis institution. Vonnegut graduated from Shortridge High School in Indianapolis in May 1940 and matriculated into Cornell University that fall. Though majoring in chemistry, he was Assistant Managing Editor and Associate Editor of The Cornell Daily Sun. He was a member of the Delta Upsilon Fraternity, as was his father. While at Cornell, Vonnegut enlisted in the U.S. Army. The Army transferred him to the Carnegie Institute of Technology and the University of Tennessee to study mechanical engineering.