A flash mob is a group of people who gather suddenly in a public place to perform a specific act, often a dance or a song, for a short period of time. These events are usually organized through social media or messaging apps, allowing participants to coordinate without revealing their plans to the public beforehand. The goal is to surprise and entertain onlookers, creating a moment of joy and spontaneity. Typically, flash mobs are choreographed and can involve dozens or even hundreds of participants. They often take place in busy locations like shopping malls, parks, or train stations. The phenomenon gained popularity in the early 2000s, with many notable examples, including those organized by groups like Improv Everywhere.