Were you one of those students who, despite your teachers’ warnings, continued to write in your books? If so, you have a lot of company—some of it illustrious (no pun intended). And now, there are a number of efforts going on around the world to capture these scribbled snippets of wisdom.

The notion of “marginalia,” or making handwritten notes and drawings in the margins of book pages, dates back as far as the Middle Ages. Presumably, monks made random drawings and notes to relieve the tedium of the manuscripts they were copying. Once mechanical printing started, marginalia really took off as scholars of the day held debates with the books they were reading—not so different from comment sections on websites.

To the despair of librarians everywhere, marginalia has marched on. “Such readers feel that they aren’t really giving a book their full attention unless they’re hovering over it with a pencil, poised to underline or annotate at the slightest provocation,” writes Mark O’Connell in the New Yorker, going on to quote George Steiner’s description of an intellectual as “a human being who has a pencil in his or her hand when reading a book.” Writers such as Jack Kerouac, Vladimir Nabokov, Samuel Beckett, Graham Greene, and Mark Twain were all noted for their habit of scribbling in books written by others.

These notes can still be useful to us today, say researchers. “This diverse evidence of annotation provides a considerable range of unique and largely untapped research materials, which reveal that readers—much as users of the internet today—adapted quickly to the technology of print: interacting intimately, dynamically, socially, and even virtually with texts,” writes Johns Hopkins University.

In fact, Johns Hopkins goes on to call marginalia “among the largest, least accessible, and most underutilized of original manuscript sources from the early modern period, due to the fact that they are almost entirely uncatalogued, or undercatalogued, by major research collections throughout the world.”

That’s what marginalia digitization projects hope to change. Here are some examples:

As people progress to reading books electronically, does this mean the death of marginalia? Just the opposite, actually. Some marginalia aficionados see it as a new revolution, equivalent to that of Gutenberg. “Imagine reading, say, Adventures of Huckleberry Finn and touching a virtual button so that—ping!—Ernest Hemingway’s marginalia instantly appears, or Ralph Ellison’s, or Mary McCarthy’s. Or imagine you’re reading a particularly thorny passage of Paradise Lost and suddenly—zwang!—up pops marginalia from a few centuries of poets (Blake, Coleridge, Keats, Emerson, Eliot, Pound), with their actual handwriting superimposed on the text in front of you,” writes self-confessed marginaliaist Sam Anderson in the New York Times. “This, it seems to me, would be something like a readerly utopia.”