Shark Tank is the American television adaptation of the business-investment format used by Dragon's Den.
The American series premiered on ABC in 2009. Entrepreneurs present companies or products to a panel of investors, called sharks, and seek investment in return for equity or another negotiated arrangement. The structure is closely related to Dragon's Den, which itself descends from a Japanese format.
Although the programmes share the same basic premise, their panelists, production, branding, and broadcast history are different. The word “shark” replaces “dragon” in the American title, reflecting the local adaptation rather than a change to the underlying concept.
The Canadian programme Dragons' Den is another adaptation and should not be confused with Shark Tank. The Apprentice is also a business-themed television programme, but it uses a different competition format and is not the American version of the investment-den concept.