An e-book (for electronic book: also ebook) is the digital media equivalent of a conventional printed book. Such documents are usually read on personal computers, or on dedicated hardware devices known as e-book readers or e-book devices.

An e-book is a specialized type of e-text.

History

Early e-books were generally written for specialty areas and a limited audience, meant to be read only by small and devoted interest groups. The scope of the subject matter of these e-books included technical manuals for hardware, manufacturing techniques, and other subjects.

Numerous e-book formats emerged and proliferated, some supported by major software companies such as Adobe's PDF format, and others supported by independent and open-source programmers. Multiple readers naturally followed multiple formats, most of them specializing in only one format, and thereby fragmenting the e-book market even more. Due to exclusiveness and limited readerships of e-books, the fractured market of independents and specialty authors lacked consensus regarding a standard for packaging and selling e-books. E-books continued to gain in their own underground markets. Many e-book publishers began distributing books that were in the public domain. At the same time, authors with books that were not accepted by publishers offered their works online so they could be seen by others. Unofficial (and occasionally unauthorized) catalogs of books became available over the web, and sites devoted to e-books began disseminating information about e-books to the public.

As of 2008, new marketing models for e-books are being developed, formats are beginning to homogenize, and dedicated reading hardware has been produced. E-books have achieved global distribution, and electronics manufacturers are releasing more e-book readers for general consumer use, such as Amazon's Kindle model or Sony's PRS-500. E-books have seen tremendous market growth in Japan throughout the 2000s and currently has an e-book market worth ¥10 billion.

Formats

main: Comparison of e-book formats

Advantages

The e-book has several advantages over physical materials:

• Text can be searched automatically and cross-referenced using hyperlinks, making the e-book format ideal for works that benefit from such functions.
• Less physical space is required to store e-books, and hundreds to thousands of books may be stored on the same device
• Because they require little space, e-books can be offered indefinitely, with no going out of print date, allowing authors to continue to earn royalties indefinitely.
• Readers who have difficulty reading printed books can benefit from the adjustment of text size and font face.
• Text-to-speech software can be used to convert e-books to audio books automatically.
• E-book devices allow reading in low light or even total darkness by means of a back light.
• An e-book may be more comfortable for some to hold because it need not be held open like a physical book and can also be set down and read without needing to be held.
• It costs little to reproduce or copy an e-book, which is ideal for archival and backup purposes.
• Ease of distributing e-texts means that they can be used to stimulate higher sales of printed copies of books.
• E-books can often be purchased from reading devices themselves and do not require one to visit a bookstore to obtain.
• Although they require electricity to be read, the production of e-books does not consume the paper, ink, and other resources that are used to produce print books.