Creeper
Credit: computerhistory.org
The first real computer virus, Creeper was released "in lab" in 1971 by an employee of a company working on building ARPANET, the Internet’s ancestor, according to Guillaume Lovet, Senior Director, FortiGuard Labs.
The Creeper looked for a machine on the network, transferred to it, displayed the message “I’m the creeper, catch me if you can!” and started over, thereby hopping from system to system.
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