An ebook is an electronic (or digital) content pages digitally bound together as a book. There are different formats of ebooks such as image file, rich text format (RTF), HTML, eXtensible Markup Language (XML), Portable Document Format (PDF), exeBook and more.

Advantages of ebooks include:

- Can be distributed instantly and at low cost over the Internet through downloads or emails.
- Text can be searched, except when represented in the form of images.
- Take up little space. Hundreds (or thousands) may be carried together on one device such as a thumb drive or CD.
- Because they take up little space, eBooks can be offered indefinitely, with no 'out of print' date, allowing authors to continue to earn royalties indefinitely (copyright law permiting), and allowing readers to find older works by favorite readers.
- Ebooks may be read in low light or even total darkness, with a back-lit device.
- Type size and type face may be adjusted by readers for better readability.
- Can be used with text-to-speech software. (See also AudioBooks)
- Instantly copied

Disadvantages:

From the user's point of view:
- Require software or hardware to read.
- Reading can be hard on the eyes
- Lacks the quality of a print book as an item

From the publisher/author's point of view:
- Can in some cases be hacked, or disseminated without approval from the author or publisher (some formats are more susceptible to this than others)
- Not normally a good format choice for works that have extensive and/or large illustrations, such as works in art history, photography, large maps, etc.

All text is available under the terms of the GNU Free Documentation License (GFDL).