Bit Rot
The slow, silent corruption of stored data over time due to hardware imperfections.
Traditional filesystems can't detect bit rot, so a photo may quietly become unreadable. Checksumming filesystems like ZFS and Btrfs detect and repair it when redundancy is present.
Related articles
Checksum
A small fingerprint of data used to detect corruption or verify integrity.
ZFS
An advanced filesystem and volume manager offering data integrity, snapshots, compression and software RAID.
ECC RAM(Error-Correcting Code Memory)
Memory that detects and corrects common data errors on the fly for greater reliability.