What is Gainsborough most known piece?

Thomas Gainsborough is most renowned for his painting "The Blue Boy," created around 1770. This iconic artwork features a young boy dressed in an elegant blue outfit, showcasing Gainsborough's mastery of portraiture and use of color. The painting exemplifies the Rococo style and has become a symbol of 18th-century British art. It is part of the collection at the Huntington Library in California.