Any device that can display text on a screen may act as an e-book reader, but specialised e-book reader designs may optimise portability, readability (especially in sunlight), and battery life for this purpose. A single e-book reader is capable of holding the digital equivalent of hundreds of printed texts with no added bulk or measurable mass.
An e-book reader is similar in form to a tablet computer. A tablet computer typically has a faster screen capable of higher refresh rates which makes it more suitable for interaction. Tablet computers also are more versatile, allowing one to consume multiple types of content, as well as create it.
The main advantages of e-book readers are better readability of their screens, especially in bright sunlight, and longer battery life. This is achieved by using electronic paper technology to display content to readers. Commercially sold electronic paper is mostly available in black and white (16 shades of gray). The Sony Librie, released in 2004 and the precursor to the Sony Reader, was the first ebook using electronic paper. First color at market's is Ectaco jetBook Color.
Many e-book readers can use the internet through Wi-Fi and the built-in software sometimes provides a link to a digital OPDS Library or e-book seller, allowing the user to buy, borrow, and receive digital e-books free through this library or seller. In this way, the books owned by the user are managed in the cloud, and the e-book reader is able to download material from any location. An e-book reader may also download material from a computer or read it from a memory card.
Research released in March 2011 indicated that e-books and e-book readers are more popular with the older generation than the younger generation in the UK. The survey carried out by Silver Poll found that around 6% of over-55s owned an e-book reader compared with just 5% of 18 to 24-year-olds.
According to an IDC study from March 2011, sales for all e-book readers worldwide rose to 12.8 million in 2010; 48% of them were Kindle models, followed by Barnes & Noble Nook devices, Pandigital, Hanvon and Sony Readers (about 800,000 units for 2010).
Some of the major book retailers and multiple third-party developers offer free (and in some third-party cases, premium paid) eReader applications for desktops and mobile devices, to allow the reading of eBooks and other documents independently of dedicated e-book devices.
In 2013 ABI Research found that the decline in the e-reader market was due to the aging of the customer base. Another reason given for this "alarmingly precipitous decline" is the rise of more general purpose tablets that provide e-books along with other apps in a similar form factor.
An idea similar to that of an e-reader is described in a 1930 manifesto written by Bob Brown titled "The Readies", which describes "a simple reading machine which I can carry or move around, attach to any old electric light plug and read hundred-thousand-word novels in 10 minutes". His hypothetical machine would use a microfilm-style ribbon of miniaturised text which could be scrolled past a magnifying glass, and would allow the reader to adjust the type size. He envisioned that eventually words could be "recorded directly on the palpitating ether".
Popular eBook readers 
- Amazon Kindle: Kindle, Kindle Paperwhite
- Barnes & Noble Nook: Nook 1st Edition, Nook Simple Touch
- Ectaco: JetBook
- Kobo: Kobo Glo, Kobo Touch, Kobo Mini, Kobo Arc
- Sony Reader
See also 
|Wikimedia Commons has media related to: E-book readers|
- Comparison of e-book readers
- OPDS Open Publication Distribution System
- Supporting platforms for e-book formats
- Falcone, John P. (August 7, 2012). "Kindle vs. Nook vs. iPad: Which e-book reader should you buy?". Crave. CNet. Retrieved January 26, 2013.
- "E-book popularity set to increase this year". Retrieved 4 March 2011.
- Nearly 18 Million Media Tablets Shipped in 2010 with Apple Capturing 83% Share; eReader Shipments Quadrupled to More Than 12 Million. Press release by IDC, 10. March 2011.
- "Tablets aren't killing ereaders, it's clog-popping wrinklies - analyst."
- "RIP e-book readers? Rise of tablets drives e-reader drop."
- "The Readies - Bob Brown - Google Books". Books.google.com. Retrieved 2012-12-06.
- Schuessler, Jennifer (2010-04-08). "Essay - Bob Brown, Godfather of the E-Reader". NYTimes.com. Retrieved 2012-12-06.