Computer viruses have come a long way, starting as the practical jokes of computing's early days and ending up as modern military weapons. A site called Computer Virus Catalog is walking through the history one virus at a time, pairing each one with a fitting illustration. The list leans heavily on the DOS era, particularly the late-’90s virus boom, and shines a light on many pivotal malware moments that have since been lost to history. And since so many of the viruses had a visual component, the artists have plenty to work with — whether it's a visualization of an email worm or the green fungus that takes over your screen to let you know you've been owned by the Lichen bug.

Each virus is also done in a different style, so you can see the playful bounce of Cookie Monster change into the frightening clash of Stuxnet. Even more surprising is how the scale of damage has grown over the years. Each bug is slightly more ambitious than the one before, until they're wiping out millions of computers, spanning continents, and calling forth an entire industry to defend against them. After Stuxnet, even the military got in on the game. What was once a simple prank is now big business or worse, a matter of national security.

Grid View Cookie Monster by Lawrence Slater First coded in 1969, Cookie Monster is considered one of the first computer viruses ever, halting all progress on a given computer until the user typed "cookie." Like most early viruses, it was built more as a practical joke than a legitimate security threat.

Techno by Joost & Nick This DOS-era bug would infect a computer's command file, then blast out 110 seconds of techno music one out of every ten times the computer started up.

Lichen by Jonathan Zawada Known for its distinctive visuals, the Lichen virus would lie dormant for a month, then take over the computer with a vivid fungal screensaver.

Happy99 by Joshua Checkley This was the first virus to move by email, and the results were staggering. By 2000, it had spread to three continents, and when a researcher posted a protective patch, more than a million computers installed it.

ILOVEYOU by Darius Ou Dahao The biggest virus of 2000 was a triumph of social engineering, causing as much as $8 billion in damage worldwide. As it turns out, people will always open an email that says "ILOVEYOU."

Stuxnet by Mel Nguyen The first computer virus used as an international weapon, Stuxnet targeted a single Iranian nuclear reactor, kicking off a new era of cyberwar in the process.



