Hook

A hook is a tool consisting of a length of material, typically metal, that contains a portion that is curved/bent back or has a deeply grooved indentation, which serves to grab, latch or in any way attach itself onto another object. The hook's design allows traction forces to be relayed through the curved/indented portion to and from the proximal end of the hook, which is either a straight shaft or a ring for attachment to a thread, rope or chain, providing a reversible attachment between two objects.

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