Shark Tank is the American adaptation of the investment-pitch format used by Dragon's Den.
The American programme features entrepreneurs presenting businesses to a panel of wealthy investors, who may offer money in exchange for equity. The investors are called sharks, creating the show's title and distinguishing its branding from the dragons used in the British version.
Shark Tank premiered in the United States in 2009 on ABC. It was based on the international format associated with Dragon's Den, which itself originated with the Japanese programme Money Tigers. The programmes share a structure but are separate national productions.
A frequent mix-up is to call Shark Tank the American title of the British show. It is more accurate to describe it as the American adaptation: its investor line-up, presenter history, companies and episode outcomes belong to the US series, not to Britain's Dragon's Den.