The term "eBook Format" refers to a digital file that can be read on an electronic device such as a computer, tablet or e-reader. Ebooks are designed in a specific file format which determines how they will appear and function on different devices. Some common formats include PDF, MOBI, EPUB, and AZW3. The choice of the right format is important for seamless reading experience as it affects font size, style, layout, reflowability, and other features.