The beach is a dynamic, ever-changing environment. Although it can be fun, it can also be unpredictable and dangerous to people who are unaware of the hazards that can be present at times. That’s why trained lifeguards who understand the beach use a system of flags and signs to advise the people with the important things they need to know. The red & yellow flag means that people can swim on the part of the beach clearly identified between the red and the yellow flag. Torn flag found on « Le Prado » beach in Marseilles France after a powerful winter storm.