A Ponzi scheme is an investment fraud that involves the payment of purported returns to existing investors from funds contributed by new investors. Ponzi schemes often share common characteristics, such as offering overly consistent returns, unregistered investments, high returns with little or no risk, or secretive or complex strategies.
This arrangement gives investors the impression there is a legitimate, money-making enterprise behind the subject’s story, but in reality, unwitting investors are the only source of funding.
A computer worm is a standalone malware computer program that replicates itself in order to spread to other computers. Often, it uses a computer network to spread itself.
The worm uses holes in a target computer’s security. 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.
On November 2, 1988, Robert Tappan Morris unleashed what became known as the Morris worm, disrupting an estimated 10% of the computers then on the Internet.