What does it mean when someone has 20/20 vision?

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  • American Optometric Association. "Visual Acuity: What is 20/20 Vision?" 
  • National Institutes of Health, Medline Plus Medical Encyclopedia. "Visual Acuity Test.
  • NDT Research Center. "Visual Acuity of the Human Eye."
  • Strouse Watt, Wendy. "How Visual Acuity is Measured." Macular Degeneration Support.

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