Darts are airborne ranged weapons. They are designed to fly such that a sharp, often weighted point will strike first. They can be distinguished from javelins by the presence of fletching (feathers on the tail) and a shaft that is shorter and/or more flexible. Darts can be propelled by hand or with the aid of a hand-held implement such as a blowgun. They can be distinguished from arrows because they are not used with a bow. Darts have been used since pre-history. The plumbatae were lead-weighted darts thrown by infantrymen in Antiquity and the Middle Ages. Darts can be propelled by a number of means. The atlatl uses leverage to increase the velocity of the dart, the kestros increases the range of propelled darts using a sling, and the exhalation of a person's breath through a blowgun propels small stone points or poisoned needles with pneumatic force. In the modern era, darts have been used for recreation; in lawn darts and the game of darts. History Pre-history Some of the earliest evidence of advanced tool use includes remnants of an early type of dart, which can be considered the ancestor of arrows as well as bows. Reconstructions of this system have a range of over one hundred metres (yards) and can penetrate several centimetres of oak. This technology was used worldwide from the Upper Palaeolithic (late Solutrean, c. 18,000–16,000 BC) until the development of archery made it obsolete. The darts in question are much larger than arrows, but noticeably lighter than javelins. They have a weighted point, often of stone, on a removable foreshaft. This is held by friction onto a thin, flexible main shaft a few metres in length, with fletching and a (usually socket-like) nock at the opposite end. Since they are unlike anything in Western history, the term "dart" has been adopted after some debate. Some alternate terms for this missile have included the spear, but this term has fallen out of favour since in all other uses, spears are stiff enough to be used for stabbing. In its function, an atlatl dart is more like a combination between a bow and an arrow. Its similarity to a bow may not be immediately obvious, but in fact both serve to accumulate energy by elasticity in a similar way. As throwing begins, a dart of this type is designed to flex in compression between the accelerating force at