Shark Tank is the United States version of the Dragons' Den television format.
The American reality business series premiered on ABC in 2009. Entrepreneurs present companies or products to a panel of wealthy investors, who may ask questions, negotiate terms and offer money in exchange for an ownership stake. The investors are called Sharks rather than Dragons, reflecting the American title.
Shark Tank is part of the wider international franchise that originated with the Japanese programme Money Tigers. Dragons' Den became the title used by the UK version and several other national adaptations, while the US production adopted its own branding and terminology.
A common mix-up is to treat Shark Tank as an unrelated programme because its panel and presentation style differ from the British series. It is instead an adaptation of the same core format. The US show has also had guest investors alongside recurring Sharks, so its panel has changed over time.