Onshore, however, you will likely find a flag warning you of potential dangers, and whether it's purple, yellow, red or blue can tell ... to keep an eye out for black-and-white flags.

or a red and yellow flag? Also, what should you do if a black and white flag looms over your favorite stretch of sand? Here’s a handy guide to 11 flags you could encounter during your next beach ...

Furthermore, this color palette was chosen so that all country flags would have ... rings colored blue, yellow, black, green ...