The inventor of the first e-book is not widely agreed upon. Some notable candidates include the following:

The first e-book may be the Index Thomisticus, a heavily annotated electronic index to the works of Thomas Aquinas, prepared by Roberto Busa beginning in the late 1940s. However, this is sometimes omitted, perhaps because the digitized text was (at least initially) a means to developing an index and concordance, rather than as a published edition in its own right.

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