Knowledge Center
EPUB & Production
Learn how EPUB works, how reflowable books differ from fixed-layout files, and why validation and semantic structure matter.
Guide
What Is an EPUB File?
A plain-English explanation of EPUB, what is inside the file, and why it is the standard format for reflowable ebooks.
Guide
EPUB 3.3 Explained in Plain English
What EPUB 3.3 means for authors and publishers, what changed, and why a standards-compliant file still needs good production decisions.
Guide
Reflowable EPUB vs. Fixed-Layout EPUB
Choose the right ebook layout model based on what the content needs readers to control and what must remain spatially fixed.
Guide
What Is EPUBCheck and Why Does It Matter?
Learn what EPUBCheck validation can catch, what a clean report means, and what validation cannot tell you about reader experience.
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Send the manuscript, cover, and publication details. We will identify the right production path before work begins.