In 1467, Peter Sch?ffer and Johann Fust published a translation of St Augustine’s The Art Of Preaching. They were old colleagues of Johannes Gutenberg, the pioneer of modern printing. But their true claim to fame is that they were the first commercially successful printers, and this success stemmed in part from their relentless innovation with the world’s newest communications technology: the book.

One such innovation appeared in the 1467 edition, which was the first printed book to include an alphabetical index. Sch?ffer and Fust were not only competing by releasing new titles. They were changing what it meant to use and read a book.

Some of the first book advertisements – and indeed some of the first modern adverts anywhere – talked up their “better arranged indexes” as a selling point. The publishers of the The Art of Preaching claimed that their indexes, along with other new cross-referencing features, were “alone worth the whole price, because they make it much easier to use”.