Robert Tappan Morris, a Cornell University computer science graduate student, was indicted for unleashing what became known as the Morris worm, the first computer worm on the internet.
A computer worm is a self-replicating malware computer program that uses a computer network to send copies of itself to other nodes (computers on the network), and it may do so without any user intervention. Unlike a computer virus, it does not need to attach itself to an existing program. Worms almost always cause at least some harm to the network, even if only by consuming bandwidth, whereas viruses almost always corrupt or modify files on a targeted computer.
Like a number of early bits of malware, the Morris Worm’s creator insists that he didn’t design it with the intention of harming computers. Instead, the worm was apparently created with the intention of measuring the size of the Internet. The result, however, was one of the earliest Internet-distributed worms, disrupting perhaps 10% of the computers then on the Internet, and Morris became the first person tried and convicted under the 1986 Computer Fraud and Abuse Act.