Jugendstil literally means "youth style". It's the German name for a movement among artists that was strongest at the end of the
19th century and the beginning of the 20th. Nearly all kinds of art were influenced by it:
painting,
sculpting,
architecture and even literature.
The root of Jugendstil was the increasing prevalence of industrialization in everyday life. Traditional art seemed unsuited to deal with in. Jugendstil artists wanted to bring back nature into industrialized life (by using plant and animal motives), and mysticism was also popular. Some of them, especially the architects, tried to "reconcile" art and everyday life by creating entire houses or useful items (such as lamps or chairs) as artworks.
Important Jugendstil artists were Gustav Klimt, Josef Maria Olbrich, Antonio Gaudi, Emile Galle, Henry van de Velde, Victor Horta.