A Slinky is a toy that consists of a pre-compressed helical spring. It was invented by Richard James in the early 1940s. It can perform a number of tricks, including travelling down a flight of steps end-over-end as it stretches and re-forms itself with the aid of gravity and its own momentum, or appearing to levitate for a period of time after it has been dropped. These interesting characteristics have contributed not only to its success as a toy in its home country of the United States, but also in other countries as well.
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