March 15– Vice-president José Sarney, upon becoming vice president, assumes the duties of president of Brazil, as the new president Tancredo Neves had become severely ill the day before. Sarney would later become Brazil's first civilian president in 21 years, upon Neves' death on April 21.[24]
March 16– Lebanon hostage crisis: US journalist Terry Anderson is taken hostage in Beirut; he remains a prisoner until December 4, 1991.[25]
April 23 – Coca-Cola changes its formula and releases New Coke. The response is overwhelmingly negative and the original formula is back on the market in less than three months.
May 9 – The 3rd total Victory Day Parade (the first being in 1945 and the next in 1965) is held on Red Square in Moscow in the Soviet Union. It features T-34-85 tanks, veterans of World War II from Poland, Czechoslovakia and the Soviet Union, and is the first parade to be held during the reign of Mikhail Gorbachev.
June 23 – Air India Flight 182, a Boeing 747, is blown up by a terrorist bomb 31,000 feet (9,500 m) above the Atlantic Ocean, south of Ireland, on a Montreal–London–Delhi flight, killing all 329 aboard.[44]
November 20 – Microsoft Corporation releases the first U.S. release of Windows 1.0, as version 1.01.[56] International support comes with the release of Windows 1.02 in Europe in May 1986.[57]
The Organization of Ibero-American States for Education, Science and Culture (Spanish: Organización e Estados Iberoamericanos para la Educación la Ciencia y la Cultura; OEI) is created.
December 11 – Hugh Scrutton is killed outside his Sacramento, California, computer rental store by a Unabomber explosive, becoming the first fatality of the bombing campaign.
Roach, Kent (2011). "The Air India Report and the Regulation of Charities and Terrorism Financing". The University of Toronto Law Journal. 61 (1): 46. doi:10.3138/utlj.61.1.045. JSTOR23018688.
Fineberg, Jonathan David (2004). Christo and Jeanne-Claude: On the Way to The Gates, Central Park, New York City. Yale University Press. ISBN978-0-300-10405-9.