Generally speaking, the first computer virus that is released to vulnerable computers was the Creeper virus. The Creeper virus has infected its predecessor on the Internet, ARPANET, a computer network. This came back in the early 1970's. The virus is not malicious because it does not hurt the affected computers, but the infected machines show the message: "I am CREEPER: Include if you know."
Creepert has undoubtedly caught the first piece of antivirus software ever created. This program was called Reaper (like in Grim Reaper) and searched for Creeper-infected computers and properly disposed of. The Reaper program was not like virus protection programs today, but it was actually the virus itself, because it replicated itself and spread over the network. (About a year ago, we discovered biological viruses that could infect other biological viruses.)
There are a lot of rumors among the authors of The Creeper and The Reaper, and many suspect that they are the same person. His (oriental) motivations are considered to be a joke, a scientific experiment that is free and even blackmailed. Anyone has succeeded in keeping this from the general public, which in itself is remarkable.
An alternative is that not one person did it. There was considerable military involvement in the ARPANET network and one of the aspects of ARPANET's research was to examine whether the system was robust enough to withstand the nuclear war and still provide a communication network. Both Creeper and The Reaper were military attempts to test network vulnerability and defense. This certainly explains why the creator's identity did not arise.
Following the first battle between the virus and the virus breaker, there is a growing number of viruses and increasingly sophisticated antivirus software . There are so many viruses and other malicious programs that hide in the hidden corner of the Internet that running an unprotected computer is uncertain.