Computer vandalism involves programs that execute malicious functions such as data extraction or erasure of hard disks, differing from viruses that attach to existing programs. It is perpetrated by various individuals, from skilled students to professional developers, with motivations ranging from testing skills to malicious intent. The document references the notable case of Robert T. Morris, whose self-propagating worm caused extensive disruption in 1988, leading to his prosecution under the Computer Fraud and Abuse Act.