On the subject of commentary, here is a book that is highly recommended.
In the Vineyard of the Text by Ivan Illich
From University of Chicago Press Books:
In a work with profound implications for the electronic age, Ivan Illich explores how revolutions in technology affect the way we read and understand text.
Examining the Didascalicon of Hugh of St. Victor, Illich celebrates the culture of the book from the twelfth century to the present. Hugh’s work, at once an encyclopedia and guide to the art of reading, reveals a twelfth-century revolution as sweeping as that brought about by the invention of the printing press and equal in magnitude only to the changes of the computer age—the transition from reading as a vocal activity done in the monastery to reading as a predominantly silent activity performed by and for individuals.
Learn more about commentary and its possible future here.

On the subject of commentary, here is a book that is highly recommended.

In the Vineyard of the Text by Ivan Illich

From University of Chicago Press Books:

In a work with profound implications for the electronic age, Ivan Illich explores how revolutions in technology affect the way we read and understand text.

Examining the Didascalicon of Hugh of St. Victor, Illich celebrates the culture of the book from the twelfth century to the present. Hugh’s work, at once an encyclopedia and guide to the art of reading, reveals a twelfth-century revolution as sweeping as that brought about by the invention of the printing press and equal in magnitude only to the changes of the computer ageā€”the transition from reading as a vocal activity done in the monastery to reading as a predominantly silent activity performed by and for individuals.

Learn more about commentary and its possible future here.