A '''Tractor beam''' is a fictional beam of energy which can trap objects in an energy field and manipulate them with changes in where the field is. They are classically placed on ships as a weapon, although in some science fiction stories small [[spaceship]]s used as tugs carry them.
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A '''Tractor beam''' is a technology found in science fiction stories, which involves a beam of energy that applies an attractive force on an object it is targeted at. The typical example is one spaceship using a tractor beam to grab another and either capture or tow it.
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A variation on the tractor beam is the '''Pressor Beam''', which applies a repulsive force on an object it is targeted at to push it away.
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The concept of tractor and pressor beams was popularized in the ''Lensman'' novels written by E.E. "Doc" Smith. <ref>http://www.daviddarling.info/encyclopedia/T/tractor_beam.html</ref>