FreeBSD Day, also known as National FreeBSD Day, is observed worldwide every June 19 to commemorate the launch of the FreeBSD operating system, which was developed at the University of California, Berkeley. This observance was inaugurated by the FreeBSD Foundation in 2017, marking the date in 1993 when developers officially named the technology. The history of FreeBSD dates back to 1974, when Bob Fabry acquired a UNIX source license, leading to the development of the Berkeley Software Distribution (BSD) Unix. FreeBSD has evolved into a popular open-source operating system, utilized by millions and serving as a teaching tool in universities. On FreeBSD Day, individuals are encouraged to learn about the operating system, share their experiences on social media using the hashtag #FreeBSDDay, and support the FreeBSD Foundation through donations.