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  • Deepak Gahlot thinks this is interesting:

Compare a functional requirement with a non-functional requirement.

From

Cover of SOFTWARE TESTING
  • TEST LEVELS
  • from SOFTWARE TESTING
  • by Peter Williams, Geoff Thompson, Angelina Samaroo, Peter Morgan, Brian Hambling
  • Publisher: British Informatics Society Limited
  • Released: October 2010

Note

functional requirements define the working of the software. for example a feature should work.

non functional requirement are those which deal with the performance aspect of the software