May 5 – After originating in the Philippines, the ILOVEYOU computer virus spreads quickly throughout the world.
September – First system enabling the selection, automatic downloading and storage of serial episodic audio content on PCs and portable devices, origin of the podcast, is launched by early MP3 player manufacturer i2Go.
January 31 – English doctor Harold Shipman is found guilty of killing fifteen of his elderly patients by lethal injections of diamorphine, the only British physician ever convicted of murdering his patients; he is actually considered to have killed at least 215.
June 20 – Cardiac surgeon Stephen Westaby and team at the John Radcliffe Hospital in Oxford (England) perform the first successful implant of a permanent electrical artificial heart, a Jarvik 2000 artificial left ventricular assist device, a turbine pump. The patient, psychotherapist Peter Houghton, survives for over 7 years using the machine until his death from unrelated causes.