The terms conversion, book design, and formatting are sometimes used interchangeably, which can lead to confusion… Here’s how Kdpcover sees it (also see diagram below):
Conversion implies using a converter to change your file from one format to another. For example, converting a PDF file to a .doc file. This is strictly technical and takes a matter of seconds. A lot of conversions are not perfect and can be frustrating to deal with. The Smashwords Meatgrinder is a good example of a converter, which is why they have very specific formatting requirements.
Book design refers to the layout and aesthetic appearance of a book. This includes the artistic element like flourishes, insets, etc. A book designer generally would also format the file appropriately (eg. get it print-ready) – so in that sense, they are the full package (and usually the most expensive).
Formatting is a combination of both, leaning towards the technical side of things. Kdpcover considers both the aesthetic and technical requirements during formatting (including best practices). We take a manuscript and ensure it meets the requirements of a retailer or distributor while ensuring it looks great on all devices.