April Fools’ Day, in most countries the first day of April. It received its name from the custom of playing practical jokes on this day—for example, telling friends that their shoelaces are untied or sending them on so-called fools’ errands. Although the day has been observed for centuries, its true origins are unknown and effectively unknowable. It resembles festivals such as the Hilaria of ancient Rome, held on March 25, and Holi, the Hindu spring festival celebrated on the full-moon day of Phalguna (February–March).

What are some notable April Fools’ Day pranks? Find out below.

Some have proposed that the modern custom originated in France, officially with the Edict of Roussillon (promulgated in August 1564), in which Charles IX decreed that the new year would no longer begin on Easter, as had been common throughout Christendom, but rather on January 1. Because Easter was a lunar and therefore moveable date, those who clung to the old ways were the “April Fools.” Others have suggested that the timing of the day may be related to the vernal equinox (March 21), a time when people are fooled by sudden changes in the weather.

There are variations between countries in the celebration of April Fools’ Day, but all have in common an excuse to make someone play the fool. In France, for example, the fooled person is called poisson d’avril (“April fish”), perhaps in reference to a young fish and hence to one that is easily caught; it is common for French children to pin a paper fish to the backs of unsuspecting friends. In Scotland the day is Gowkie Day or Hunt the Gowk; the gowk, or cuckoo, is a symbol of the fool. On the following day (Tailie Day) signs reading “kick me” are pinned to friends’ backs. In many countries newspapers and the other media participate—for example, with false headlines or news stories.

Notable April Fools’ Day pranks

• In what may be the first televised April Fools’ Day hoax, the BBC aired a segment in 1957 that featured spaghetti-growing trees in Switzerland. The broadcast claimed that the dreaded spaghetti weevil had been eradicated, leading to a bumper crop of spaghetti. The BBC even aired clips of people “harvesting” the spaghetti. CNN later called it “undoubtedly the biggest hoax that any reputable news establishment ever pulled.”
• The BBC was back at it in 1965 when it interviewed a professor who had invented “Smellovision,” a new technology that allowed for the transmission of aromas through a television screen. Following a demonstration, numerous viewers called the BBC to confirm that they had detected the scents.
• In 1996 Taco Bell announced that it had purchased the Liberty Bell and renamed it the Taco Liberty Bell. The restaurant chain claimed that the acquisition was to help with the U.S. debt. (The Liberty Bell is actually owned by the city of Philadelphia, though the National Park Service [NPS] maintains it.) The news upset many Americans, and the NPS was forced to hold a press conference that refuted Taco Bell’s claim.
• In 1977 The Guardian newspaper printed a travel supplement on San Serriffe, an island republic in the tropics. The text was filled with printing and typesetting terms—from the name of the island (inspired by sans serif typeface) to the shape of the island (a semicolon) to the island’s dictator, General M.J. Pica (the last name was a reference to a unit of typographic measurement).
• In 1992 NPR declared that Richard Nixon, who resigned as president in 1974 amid the Watergate scandal, was entering that year’s presidential race. The radio network said his slogan was “I never did anything wrong, and I won’t do it again.”