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Ali Azhar
Published March 21, 2022 8:15 am

Creeper is a computer virus created in 1971. It is commonly recognized as the first-ever computer virus

Where did Creeper come from?

At the time it was created, the concept of a computer virus did not exist. It was created by Bob Thomas at Raytheon BBN Technologies in 1971 as an experimental program designed to self-duplicate. 

The intention was not to cause damage, but just to demonstrate the concept of an application that could move from one computer to another. The Creeper was designed to simply move between computers by making a duplicate of itself. At the time, Creeper caused the malfunctioning of installed printers on several DEC PDP-10 mainframe computers that were running on the TENEX operating system. Creeper was named after a bank robber character in the 1970s cartoon “Scooby-Doo”.

How does Creeper work?

The Creeper virus was not malicious software so it did not cause any damage per se. It caused issues with the installed printers by displaying the message “I’M THE CREEPER, CATCH ME IF YOU CAN”. 

To understand how the Creeper worked, one needs to understand ARPANET, which was the precursor to the internet.

Developed by the United States Department of Defense, ARPANET was designed to communicate between computers over a long distance, without needing a phone connection. ARPANET accomplished this by using packet switching. Creeper was created to be a computer “worm” that would replicate itself and spread to other systems, in particular, the Digital Equipment Corporation (DEC) mainframe computers that were using ARPANET. 

The Creeper did not steal or destroy any data, it simply displayed the message on the screen. A key difference between Creeper and a typical computer virus is that Creeper was designed to erase its old versions as it duplicated itself. Although the Creeper virus only affected 28 devices, it’s said to have launched the cybersecurity industry.

What is the connection between Creeper and Reaper?

The Reaper is the nemesis of the Creeper virus as it was created as an anti-virus program to fix the Creeper virus. The Reaper was created by Ray Tomlinson and was first released in 1972. The Reaper was designed to erase the Creeper program from the computer.

As the Creeper is recognized as the first computer virus, the Reaper is considered as the first anti-virus computer program, which is commonly used in the modern computing world. The word reaper means “pruner,” making it a suitable name for an antivirus program. The historic connection between Creeper and Reaper was the inspiration for the popular programming game Core War.