An example of a succesful hoax is "A teacher pretends to give failing grades to her students and then laughs at their reactions."
A hoax refers to a falsehood fabricated to masquerade as the truth. It is distinguishable from errors in observation or judgment, rumors, urban legends, pseudosciences. In other words, it is a humorous or malicious deception.
According to the English philologist Robert Nares, the term hoax was coined in the late 18th century as a contraction of the verb hocus, which means "to cheat."