Indian Navy Day 2021- Why is it celebrated on December 4?

Indian Navy Day 2021: Navy Day is celebrated on this day to mark the anniversary of Operation Trident which was launched by the Indian navy during the Indo-Pak war in 1971. Also, read about 5 facts related to the Indian Navy and the names of some of the major Indian Navy Ships. 

source https://www.jagranjosh.com/current-affairs/indian-navy-day-2021-why-is-it-celebrated-on-december-4-1638600192-1