Elk Cloner was the first computer virus known to have spread in the wild. Richard Skrenta, then fifteen years old, wrote the virus for the Apple II operating system, which was stored on floppy diskettes. When a computer booted from a floppy disk infected with Elk Cloner, the virus would start, and would subsequently copy itself to any uninfected floppy disk that was accessed. Because computers of that time had dual floppy disk drives, and because diskettes were often passed around among friends, the virus was frequently copied. After contagion, every 50th time that a computer booted up, it would display the following text:

It will get on all your disks
It will infiltrate your chips
Yes it's Cloner!

It will stick to you like glue
It will modify ram too
Send in the Cloner!

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