A tool is any item that can be used to achieve a goal, especially one that is not consumed in the process. Informally the word is also used to describe a procedure or process with a specific purpose. Tools that are used in particular fields or activities may have different designations such as Instrument, Utensil, Implement, Machine, or Apparatus. The set of tools needed to achieve a goal is equipment. The knowledge of constructing, obtaining and using tools is technology.
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