Accessing e-books requires a desktop or laptop computer, tablet, smartphone, or a proprietary e-reader device. Proprietary e-reader devices work best with their proprietary files. If you do not own a specific e-reader for example, a Kindle, Nook, or Kobo reader, free software applications are generally available for download to other devices to read files designed for the proprietary devices. Before accessing e-books, be sure to check what file format is most compatible with your preferred reading device. Then check your device's website and app store to find the appropriate applications for the other e-book formats you want to use.
PDF (portable document format), .txt (plain text) files, or web browser formats will likely be the most compatible for most devices for e-books, but these will lack special features offered by the other formats. For audio books, the most popular file format is MP3, which is widely supported on nearly all devices. Some e-books are available in the M4B format, which allows for bookmarking and is available for free download. A few other formats available require proprietary devices or a special software, which may be free.
Most e-book websites have more than one search or browse option. Some allow users to limit their searches to titles and/or authors; some allow full-text searching; some allow both. Some offer browse lists. Here are some tips for searching the Library of Congress resources.