e-Readers may be specifically designed for that purpose, or intended for other purposes as well. The term is restricted to hardware devices and used to describe a category type.
Specialized devices have the advantage of doing one thing well. Specifically, they tend to have the right screen size, battery lifespan, lighting and weight. A disadvantage of such devices is that they are often expensive when compared to multi-purpose devices such as laptops and PDAs.
In 2010, competition sent the price for the most popular electronic reading devices below USD 200.