There has been some discussion in a number of places of the recent announcement of the Vesuvius Challenge 2023 Grand Prize, which was given for proof of successful scanning and reading of a one of the carbonized Herculaneum scrolls without unrolling it. The Vesuvius Challenge was to recover at least 85% of the characters from four passages of at least 140 characters each; given the state of the scrolls, no one was even sure whether it could be done. The Grand Prize winners -- Youssef Nader, Luke Farritor, and Julian Schilliger -- were able to offer multiple passages for a total of over 2000 characters. I thought I would informally compile some of the basic background information here; everything I say here can be found in many other places, although some of it is very scattered.
Herculaneum was a town near Pompeii that, like Pompeii, was buried when Mount Vesuvius erupted in AD 79. It was accidentally rediscovered in 1709. Herculaneum is interesting in that it was a much wealthier town than Pompeii, essentially a seaside community for wealthy Romans. Most of it has not been excavated, but of what has, the most important is what is usually known as the Villa of the Papyri. We don't know who owned it, although the best guess at present is that it was the property of the Piso family (which is significant for reasons we will see later); it was an extremely grand, palatial building. The Villa of the Papyri gives us the single largest collection of ancient statues from Rome, but, as the name suggests, far more valuable was the discover in the 1750s of a very large collection of papyri. Papyrus does not generally survive well in a Mediterranean climate, but here was ironically saved by the volcanic eruption, which carbonized the scrolls and buried them in low-oxygen conditions much more favorable to their survival. All of the scrolls seem to have been in storage -- it's usually assumed that they were stored in order to move to safety, but for all we know, it could very well be that it was no longer a library in active use at all.
We don't know for sure how large the original collection was; some of it may not have survived at all, and the surviving papyrus is all very easily damaged and destroyed. We know for a fact that many scrolls were destroyed or damaged in excavation (some were just thrown away as debris) and many others have been destroyed or damaged by attemtps to read them since the eighteenth century. What does survive ranges from fragmentary scraps to more-or-less intact scrolls. The question of how to unroll the actual scrolls has always been a problem. Physically unrolling them tends to destroy them, and once everything inside becomes exposed to air, it begins deteriorating. Early on, Abbot Piaggio of the Vatican Apostolic Library was the first person actually to manage to unroll one, rather than just slicing it into fragments, by inventing a machine that unrolled it so slowly that it took four years to unroll. But it was always risky business; one wrong move, and the whole thing could crumble, and every scroll being quite different, methods that would work for one would be disaster for antoher. Once you unroll them, of course, you then have the difficult task of deciphering what they say. This is made quite challenging by the fact that most of the scrolls are written in carbon-based ink on a now-carbonized papyrus. And, of course, the clock is ticking, because, exposed to the air, the barely legible ink begins to break down and fade.
Modern techniques have not actually put us much further, running into the same problems. Even our best physical unrolling methods are risky gambles that can destroy the scroll. So the focus has switched to scanning and then using computer algorithms to interpret the results. Researchers still run into difficulties on both points. Our usual best scanning methods for something like this can give us a good picture of internal structure of the scroll, but are usually unable to distinguish carbon-based ink on carbonized papyrus. However, we do get something; X-ray phase-contrast tomography can get us some way toward distinguishing even the carbon-based ink, although not very crisply or always very consistently, and some of the scrolls have turned out to use an ink that was not purely carbon-based (using lead, for instance), which gives better results. Even then, however, the internal structure of a carbonized scroll is extremely complicated, often well beyond what our available computer programs have been able to handle. So for the past decade or so, major effort has been expended on developing programs capable of interpreting these really messy, complicated scanning results by analyzing the data to detect ink and 'digitally unroll' the entire thing. There have been many failures along the way; when the Vesuvius Challenge was announced, there was no general expectation that it would succeed. The announcement on February 5 was exciting because the recent push had results massively better than expected.
The content of the most recent scroll -- currently about 5% read -- has not been released yet, but it is a work on Epicurean philosophy, very possibly a previously non-extant work by Philodemus of Gadara, who lived in the first century BC. This is not unexpected. The collection from the Villa of the Papyri has been known almost since the beginning to be a collection heavily focused on Epicurean philosophy, with a significant portion being works by Philodemus. And it has generally been thought for quite a while that at least part of the collection is Philodemus's own library; some of the lectures by him that have already been deciphered have corrections that go beyond mere corrections; if not Philodemos's own corrections, they are very likely those of a student who knew him.
Outside of the papyri, Philodemus is not known except for some epigrams and some very brief and passing mentions by Cicero and by Diogenes Laertius. Cicero attended lectures by Zeno of Sidon, who was Philodemus's own teacher, and may have known him directly, although they are unlikely to have had any extensive acquaintance, since Philodemus was associated with Julius Caesar's father-in-law, Lucius Calpurnius Piso Caesoninus, who became one of Cicero's political enemies.
How the collection ended up in Herculaneum is not strictly known. There are three major hypotheses that have been proposed.
(1) Philodemus had an Epicurean school in Herculaneum, so that the Villa of the Papyri was his. This is the least likely of the three. The Villa of the Papyri, remember, is palatial even for the Roman equivalent of a wealthy seaside resort; the owner would have had to have been one of the wealthiest men in Italy. One of the epigrams by Philodemus that has survived is an invitation to Piso to attend a dinner at Philodemus's shack; this is almost certainly an exaggeration, but it emphasizes the point that Philodemus was a philosopher in need of patrons to support his lifestyle.
(2) The Villa was owned by L. Calpurnius Piso Caesoninus. This is far and away the most likely possibility. The Piso family was a wealthy family with extremely good connections, and Piso himself is known to have been a patron of Philodemus. If the collection was just in storage because it was not being used actively, this would explain other features of the find, and would also make sense on this hypothesis -- the Piso family would have inherited Piso's own philosophical library, and would have therefore had reason to keep it even if they were not using it.
(3) It's just possible the Villa was owned by someone else; in which case they were collectors of Epicurean philosophical texts, and at some point acquired what seems to be Philodemus's own library.
In any case, Philodemus was not a major philosopher, as can be seen by the fact that we only barely have any mention of him elsewhere, and in a number of his works he is simply presenting the views of his teacher, Zeno of Sidon; his primary significance is that he seems to have done an extraordinary amount of research into the works of Epicurus and other major figures in the Epicurean school, making him perhaps the best possible source for understanding the doctrines and debates of Roman-era Epicureanism. However, as such a conduit he has had some influence on the course of philosophy since the discovery of the Herculaneum Papyri. David Blank has a nice discussion of Philodemus's philosophy, with some interesting discussion of the Herculaneum Papyri themselves, in his 2019 SEP article on Philodemus.
The Wikipedia article on the Herculaneum Papyri is actually quite helpful, and I found it very useful for keeping various things straight.