Convert EPUB to 4 (Man Page)

The EPUB (Electronic Publication) file extension is a widely utilized format for digital books and publications, leveraging its versatility across various e-readers and devices. Officially established by the International Digital Publishing Forum (IDPF) in 2007, it superseded the Open eBook standard. EPUB's structure allows for reflowable content, meaning text can adapt to different screen sizes, enhancing readability. It supports multimedia elements, such as images, videos, and interactive features, making it suitable for diverse digital publications beyond conventional eBooks. EPUB's adoption stems from its open standard, promoting broad compatibility and ease of access in the digital publishing landscape.

The 4 file extension refers to Unix Section 4 Manual Pages, which document special files and device drivers. These files, such as "mouse.4", describe how devices interact with the Unix operating system and are accessed using the "man" utility. Historically, these manual pages have been a fundamental part of Unix documentation, helping users understand and manage system devices.