Although electronic books (abbreviated e-books) were predicted a great future already several years ago, only now they are becoming really popular thanks to today’s technological advancements. Until recently, eBook readers have still been impractical devices with dimensions that had not much to do with mobility and the same went for ease of use. But over time eBook readers evolved into today's thin, compact and easy to carry models, with a memory that can hold virtually your entire library (plus you can easily expand it by using memory cards!). What's more, eBook readers can nowadays even display images and play music (mostly in the formats MP3 and WMA).