ODT would be the usual LibreOffice document. Great if you need to edit the contents.
PDF is good for sending a possibly locked down non-editable version.
EPUB is similar to PDF and targets something you would have as a book on an E-reader.
All can look good to same so no winner there.
I know nothing about document formats, all I want is to have the one that is easiest to navigate around, looks best, etc.
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