Frans Hals (1580-1666) was a Dutch Golden Age painter especially famous for portraiture. He is notable for his loose painterly brushwork, and helped introduce this lively style of painting into Dutch art.
Hals was also instrumental in the evolution of 17th century group portraiture.
Hals was a master of a technique that utilized something previously seen as a flaw in painting, the visible brushstroke.
The soft curling lines of Hals' brush are always clear upon the surface: "materially just lying there, flat, while conjuring substance and space in the eye".