The iconic image of the sailboat represents a wide variety of seagoing vessels ranging from huge sailing ships to smaller sailboards. Harnessing wind power as a driving force for movement, sailboats enabled humans to reach the most remote corners of the globe long before the advent of modern sea-faring technology. Sails were a more efficient and humane alternative to ranks of oarsmen, who were often slaves, and whose work was grueling and dangerous. Greeks, Phoenecians, and others refined the geometry and operation of multiple sails, allowing farther voyages and increased cargo capacity. Worldwide exploration, trade, conquest, and battle all relied on catching and using the wind, from Renaissance explorations of new worlds to more systematic efforts of later ages. These transformed daily life with a commerce of exotic goods, collection of hitherto unknown plants and animals, and stimulated many areas of science. Even rocketry and space exploration, limited by the meager energy available from chemical fuels and the difficulty of nuclear engines, would be vastly enabled by sails that used the stream of flowing particles called the "solar wind."