Bravo Zulu is really an open naval secret. The origins of Bravo Zulu (or BZ in short) date back to the 1940s.

Navy ships in the fleet used to pass messages by morse code and through flag signals. BZ is a combo of both the Bravo and Zulu nautical flags being flown together as a way to convey “Good job or well done” between ships.

Bravo Zulu has been adopted by mariners across the globe as a universal signal as this short video below demonstrates.

Like many military sayings, Bravo Zulu has entered military slang and is used during all sorts of ceremonies. It has even been known to show up in written form in someone’s performance evaluation as a “BZ for a job well done…” Taking about climbing the ranks!

Flags are still used as a method of communication between ships today as well. They are a good and simple backup to radio and wireless communications.

Want to see how communication officers work at sea? This classic declassified us Navy video below gives you an idea: