There were guides and forums, strangers with patient hands writing lore in the margins. "Dump with 4x speed," they said, "verify with checksums." I learned checksums the way sailors learn constellations; a hash told me whether a file had been true on the journey from disc to byte. I learned to compare with known good images, to prefer files with provenance — dumps taken from original discs, logged with serial numbers and region codes, the metadata like an heirloom tag.