Nowadays, books come to the spirit food to people. 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). You can see books are sold with barcode labels on the back in markets.

Books may also refer to works of literature, or a main division of such a work. In library and information science, all the books must have a special barcode labels to scan, and this can help the administrator to know who borrowed the books well, 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 — an avid reader of books.

A shop where books are bought and sold is a bookshop or bookstore. Books can also be borrowed from libraries. Google has estimated that as of 2010, approximately 130,000,000 unique titles had been published, and these published books must have barcode labels on.

The word comes from Old English "bōc" which 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, another Slavic languages, the words "букварь" (bukvar') and "буквар" (bukvar), respectively, refer 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.[3] Similarly, the Latin word codex, meaning a book in the modern sense (bound and with separate leaves), originally meant "block of wood".