According to Wikipedia , EPUB is an open e-book standard developed by the International Digital Publishing Forum and currently maintained by the World Wide Web Consortium. Technically, an EPUB file is essentially a containing web-based content such as HTML5, CSS, and images. This structure allows it to function much like a website contained within a single file, making it highly adaptable to various software environments. Reflowable Content: The Key Advantage

The EPUB standard is built with as a core pillar. It supports semantic markup that allows assistive technologies, like screen readers, to easily navigate document structures. Features like text-to-speech support and metadata for book information ensure that digital literature is inclusive for users with visual impairments. Furthermore, because it is an open standard, it is supported by a vast array of devices and software, from specialized e-readers like Kobo to versatile applications like Adobe Digital Editions . Conclusion

Readers can change font types, increase text size, or adjust background themes (such as "dark mode") to suit their personal preferences and environment. Accessibility and Universal Support

What is an .EPUB file and how do I open and view one? - Adobe

Whether reading on a large tablet or a narrow smartphone, the text remains perfectly sized.

The Digital Reading Revolution: The Evolution and Impact of the EPUB Format