The Myth of Digital Permanence
Digital information is often conceptualized as "immortal"—perfect copies that never degrade. In reality, the physical substrates that hold our data are subject to the same laws of thermodynamics as a paper book or a stone tablet.
Hard drives demagnetize (hysteresis). Flash memory leaks charge. CD-ROMs suffer from "disc rot," where the reflective aluminum layer oxidizes and peels away like dead skin. The data is not lost all at once; it "rots" bit by bit. A single flipped bit in an uncompressed image might just change a pixel's color; a flipped bit in a compressed archive (like a zip file) can render the entire structure unreadable.
Types of Degradation
The archaeobytologist encounters Bit Rot in three primary forms:
1. Media Decay (Disc Rot)
The physical breakdown of the storage medium. CD-Rs from the 1990s are now reaching the end of their chemical lifespan, with the organic dye layer fading or the metallic layer oxidizing ("bronzing").
2. Data Corruption (Silent Corruption)
Errors introduced during file transmission or writing. Without error-correcting code (ECC), a file can change simply by sitting on a hard drive for a decade as magnetic domains drift.
3. Software Rot (Code Rot)
While often used interchangeably, this is distinct. Software rot refers to code that stops working not because the bits changed, but because the environment around it changed (see: API Petrifaction). True Bit Rot is purely physical/magnetic entropy.
Field Notes
The Toy Story 2 Near-Disaster: In 1998, a command (`rm -rf`) accidentally deleted 90% of the movie's files. The backup system had been silently failing for months due to a corrupted tape drive—a form of systemic rot. The movie was only saved because the technical director, Galyn Susman, happened to have a copy on her home computer for telecommuting.
Cosmic Rays: Bit flips can be caused by high-energy particles from space striking a microchip. In 2003, a Belgian election was briefly thrown into chaos when a single bit flip in an electronic voting machine gave a candidate exactly 4,096 extra votes (2^12).
Ephemera
The "M-DISC" was an attempt to solve this by etching data into a rock-like layer, theoretically lasting 1,000 years. However, finding a drive that can read an M-DISC in the year 3025 remains a separate problem of "Hardware Extinction."