If a picture is worth a thousand words, then the British Library’s most recent digitization effort is worth 4 billion words. Attempting to preserve manuscripts, records, newspapers, photographs, sound archives and even inscriptions in rock that are at risk of loss or deterioration, the Endangered Archives Program (EAP) has made four million images available online.

The EAP, established in 2004, has so far financed 246 projects in 78 countries, writes the New York Times. The data amounts to more than 200 terabytes.

Of course, the British Library isn’t alone in its efforts. Many libraries, including the Vatican, are scanning their holdings and putting them online to preserve and protect them, as well as make it easier for people to gain access to them. But the EAP’s efforts focus on digitizing material in situ, which it obtains by offering grants to organizations with access to such collections.

“The Endangered Archives Program uses digitization to preserve records and to make them freely accessible to all, without removing original materials from their custodians,” the organization writes in its blog.

“Whenever possible the projects help the keepers to secure the survival of the original documents. Because the materials are often too fragile to be handled on a regular basis, the digital surrogates frequently provide the only point of access not only for scholars worldwide, but also for local readers. By making digital records available to all, the program ensures that the history they capture is open to wide audiences, multiple perspectives and diverse interpretations.”

The organization, which recently celebrated its tenth anniversary, has also published an ebook called From Dust to Digital with articles about 19 of its projects. The blog explains: “The articles tackle the fundamental problems of transcribing and translating—sometimes for the very first time—languages that have nearly fallen silent.”

During the lifespan of the EAP, the technology for collecting, sending, and storing the information has changed, director Adam Farquhar told Wired. “In the early days, we received digitized copies of endangered material on CDs and DVDs. We have tens of thousands of them. Back then, we didn’t even assume that they could be put online.”

Instead, the CDs and DVDs were stored in archives full of paper. Today, however, the organization typically receives content on hard drives and quickly moves the content onto managed storage to make it available online.

So what’s included in the pictures? The most recent collections include “popular market” Bengali books; Bolama documents from Guinea-Bissau; Yao manuscripts from Yunnan province in southern China; and Native Administration records from Malawi.

“The four million images from the program are fascinatingly diverse, both in their material and what threatened their survival,” writes Allison Meier in Hyperallergic. “There are newspapers and magazines from 20th-century Palestine, early professional photography in Mali from the 1940s–60s, and rock inscriptions from the Tadrart Acacus mountains in Libya, which have been damaged by increased visitors and oil exploration and extraction.”

For example, 700-year-old manuscripts from Keralta, India, written on palm leaves, are particularly vulnerable because, “until recently, consigning manuscripts into the sea or river on auspicious days was considered the best practice to preserve them, to avoid the sin of witnessing their decay,” EAP writes.

Consigning documents to the river makes a typical day of scanning and shredding paper sound pretty mundane.