The term "books" may also refer to a body of works of literature, or a main division of literature (e.g., children's literature) . In library and information science, a book is called a monograph, to distinguish it from serial periodicals such as magazines, journals, or newspapers. 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). An avid reader or collector of books or a book lover is a bibliophile or colloquially, "bookworm".

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A shop where books are bought and sold is a bookshop or bookstore. Books are also sold in some department stores, drugstores and newspaper vendors. Books can also be borrowed from libraries. Google has estimated that as of 2010, approximately 130,000,000 distinct titles had been published. In some wealthier nations, the sale of printed books has decreased because of the use of e-books, though sales of e-books declined in the first half of 2015.

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The word book comes from Old English "bōc", which in turn comes from the Germanic root "*bōk-", cognate to "beech". Similarly, in Slavic languages (for example, Russian, Bulgarian, Macedonian) "буква" (bukva—"letter") is cognate with "beech". In Russian and in Serbian and Macedonian, the word "букварь" (bukvar') or "буквар" (bukvar) refers specifically to a primary school textbook that helps young children master the techniques of reading and writing. It is thus conjectured that the earliest Indo-European writings may have been carved on beech wood.[5] Similarly, the Latin word codex, meaning a book in the modern sense (bound and with separate leaves), originally meant "block of wood".