WIKIPEDIA =>
the term UFO (translation from English UFO Unidentified Flying Object), refers to a phenomenon described as any object suspected steering wheel, real or apparent, which can not be identified by the observer and the origin of which remains unknown after investigation.
sightings of unusual phenomena can be traced back to antiquity, but the term became popular from the first sighting, which was released in 1947 . Since then, tens of thousands of people around the world have stated that they would have seen UFOs.
Due to numerous reports, some groups would speculate that most likely was not aware of many others because of fear of ridicule, because of the stigma that was created on the UFO issue. This is because in popular culture around the world, the term is usually used to refer to UFO shed any hypothetical extraterrestrial although the term itself really does not define the nature of the phenomenon. The term "flying saucer" is also used as an equivalent to describe a type of UFO.
When a UFO is identified as a known object, it ceases to be a UFO and becomes identified flying object. In these cases it is inaccurate to continue to use the term to describe the object.
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