This API was created at the rocketseat event, the NLW4 (Next Level Week), it is an API for sending emails with a question to users (database already made), "how much would you recommend Xcompany", and with the answer calculate the NPS (Net Promoter Score) of this company and deliver a JSON with the number of promoters, decreters, passives and the total, brings the score and what quality most benchmarks could give for this score.