Butr.zip

If you spent any time in the darker corners of the early 2000s web, you might have run into a tiny file called butr.zip . At first glance, it looks harmless—it’s only about , roughly the size of a low-res thumbnail.

When a computer tries to unzip butr.zip , it begins a recursive decompression nightmare. That 6 KB file contains layers upon layers of highly compressed data. If fully expanded, it would swell to hundreds of terabytes —far more than the storage capacity of almost any consumer computer in existence. The Result: butr.zip

The name is shorthand for "Butterfly." It’s a poetic irony: something as small and delicate as a butterfly (the 6 KB file) can cause a massive, chaotic storm (the system crash) when it "unfolds its wings." If you spent any time in the darker

Your hard drive runs out of space, causing the operating system to freeze or crash entirely. That 6 KB file contains layers upon layers