<P> A catapult is a ballistic device used to launch a projectile a great distance without the aid of explosive devices--particularly various types of ancient and medieval siege engines . In use since ancient times, the catapult has proven to be one of the most effective mechanisms during warfare . In modern times the term can apply to devices ranging from a simple hand - held implement (also called a "slingshot") to a mechanism for launching aircraft from a ship . </P> <P> The word' catapult' comes from the Latin' catapulta', which in turn comes from the Greek Ancient Greek: καταπέλτης (katapeltēs), itself from κατά (kata), "downwards" and πάλλω (pallō), "to toss, to hurl". Catapults were invented by the ancient Greeks and in ancient India where they were used by the Magadhan king Ajatshatru around the early to mid 5th Century BC . </P> <P> The catapult and crossbow in Greece are closely intertwined . Primitive catapults were essentially "the product of relatively straightforward attempts to increase the range and penetrating power of missiles by strengthening the bow which propelled them". The historian Diodorus Siculus (fl . 1st century BC), described the invention of a mechanical arrow - firing catapult (katapeltikon) by a Greek task force in 399 BC . The weapon was soon after employed against Motya (397 BC), a key Carthaginian stronghold in Sicily . Diodorus is assumed to have drawn his description from the highly rated history of Philistus, a contemporary of the events then . The introduction of crossbows however, can be dated further back: according to the inventor Hero of Alexandria (fl . 1st century AD), who referred to the now lost works of the 3rd - century BC engineer Ctesibius, this weapon was inspired by an earlier foot - held crossbow, called the gastraphetes, which could store more energy than the Greek bows . A detailed description of the gastraphetes, or the "belly - bow", along with a watercolor drawing, is found in Heron's technical treatise Belopoeica . </P> <P> A third Greek author, Biton (fl . 2nd century BC), whose reliability has been positively reevaluated by recent scholarship, described two advanced forms of the gastraphetes, which he credits to Zopyros, an engineer from southern Italy . Zopyrus has been plausibly equated with a Pythagorean of that name who seems to have flourished in the late 5th century BC . He probably designed his bow - machines on the occasion of the sieges of Cumae and Milet between 421 BC and 401 BC . The bows of these machines already featured a winched pull back system and could apparently throw two missiles at once . </P>

When was the catapult invented and by whom
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