Flash mob is a term that refers to a group of people who suddenly assemble in a public place, perform a brief spontaneous act, and then disperse. Although it originated in the early 21st century, it has quickly become a phenomenon that is recognized worldwide. However, there are several synonyms that can be used in place of flash mob. Some of these include flash mobbing, instant gathering, spontaneous assembly, impromptu performance, and guerrilla gathering. Regardless of what term is used, these events often create a sense of excitement and intrigue amongst onlookers, making flash mobs (or whatever they may be called) a unique and entertaining experience.