I worked as a "library page" in my senior year of high school. It worked out well since I had to transfer from one line of transport to another near the central (and impressive) branch of the Baltimore Enoch Pratt Free Library.
There are many branches of the library around the city and its suburbs. I was a page in the History department and my job was reshelving books that had been taken off the shelves to be used or borrowed. So, when I learned the other day of the book "A Place for Everything: a History of Alphabetical Order" by Judith Flanders, I was interested. In that job, I used alphabetical order all the time.
Flanders makes it clear that the ordering of a large number of books was an open question that was answered in different ways over the centuries. At first, it seemed sensible to librarians to put the most important books first. Books of lesser importance could be placed in less central locations. Many librairies even today have a special shelf near the entrance for books that have just recently been added to the collection.
I read that if you knew of a certain book, in ancient libraries, your best bet was to ask the librarian, who often knew where a book was. Our modern tools of simply going to the Amazon site and telling it to send the book to your Kindle with a cellphone call would probably have been literally unbelievable. We still have strong limits on what we can do, since so many good, attractive and desired books are not available in electronic form. We can install Kindle, Nook, Kobe and other software on a single computer, a tablet or a phone and get books from different sources, including local libraries that can also send books through the air electronically.
Flanders explains that it took some additional centuries before it became understood that to alphabetize Hubert, Humbert and Hume, we can look at 2nd and 3rd letters, at all the letters in a word, and use those letters also to decide which comes before what.