Of course, with the rapid growth of the number and popularity of books, methods to store books needed to be devised, so the bookcase, or bookshelf, was born. Originally, before the invention of mass printing and the modern book that we know and take for granted today, people who could afford expensive, rare and valuable manuscripts would keep them in cupboards or simple shelves–the origin of the modern bookshelf.
Bookshelf and bookcase are synonyms and can be used interchangeably, although there may be slight differences, notably that a bookshelf is by definition open-fronted, whereas bookcases may have doors and can be closed. For the convenience of the reader, these doors are often made of glass, or have windows on them, so that the book spines can be read. The art and trade of bookshelf- and bookcase making has a long history and a rich tradition; as with any other piece of furniture, the wealthy and noble classes in history (who were usually also the only ones who could read, as well as the clergy) have created a demand for beautiful, ornate bookcases that were esthetically pleasing, as well as durable and practical. The most common material for bookcase-making is still wood, and while more modern plastic and metal alloy bookcases exist, wooden bookshelves are considered to be by far the most elegant and desirable. Traditionally, wooden bookcases have been made of oak, still the wood of preference today for the traditionally-minded. Other exotic, as well as practical types of wood have also been used over the years; examples include mahogany, satinwood and rosewood, and decorative elements of bronze and occasionally marble are not unheard of.
Bookcases are also a prominent part of fiction, particularly in certain mystery stories where secret rooms or compartments are often hidden behind them. Stereotypical to these bookcases is that they reveal the hidden room when the owner removes a particular book or books from the bookshelf.