A user wants to access books and does not need printed, physical copies. The solution should be portable and lightweight. Which of the following is the best solution?

An e-reader is a portable electronic device specifically designed for reading digital books (e-books). These devices are characterized by their lightweight design and specialized screens (often E Ink) that mimic the appearance of paper, making them ideal for extended reading sessions. They meet all the user's requirements: accessing digital books, portability, and being lightweight, without the need for physical copies.

B. Servers: Servers are powerful computers designed to provide services over a network; they are not portable or intended for personal reading.
C. External drive: An external drive is a storage device and requires a separate computer or reader to access its content; it is not a reading device itself.
D. Workstation: A workstation is a high-performance computer, typically stationary and heavy, designed for demanding tasks, not for portable reading.

1. MIT OpenCourseWare, Course 6.0001: Introduction to Computer Science and Programming in Python, Fall 2016. In lecture materials discussing various computing devices, e-readers are classified as specialized portable devices for content consumption, contrasting with general-purpose computers like workstations or backend infrastructure like servers. (Reference: General classification of computing devices in introductory computer science curricula).

2. Purdue University, College of Liberal Arts, "E-textbooks: The Nitty Gritty." This resource discusses various platforms for accessing digital academic texts, explicitly identifying e-readers like Kindle and Nook as primary devices for this purpose due to their portability and specialized displays. (Reference: Section on "Devices for Reading E-textbooks").

3. University of Washington, UW-IT, "Accessible Technology - E-readers." This documentation describes e-readers as "handheld devices designed primarily for reading digital publications." It highlights their portability and features like E Ink screens as key advantages for readers. (Reference: Section "What is an e-reader?").