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The Morris Worm

1988

The Morris worm emerged before most people knew there was an Internet. It was created not to cause any disruption but to measure the size of the Internet by propagating itself across the network. One side effect: It slowed computers down to the point of being useless. It affected some 6,000 computers, a high number for the time. Its creator, Robert Tappan Morris, then a student at Cornell University, was later sentenced to three years of probation. He's now a professor of computer science at the Massachusetts Institute of Technology and a co-founder of Y-Combinator, a tech incubator that helps startups get off the ground.

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