Why Red sea is known as Red sea?

One of the world’s  most iconic scuba diving locations is undoubtedly the Red Sea, an inlet  of the Indian Ocean that lies between Africa and Asia. It’s  renowned for its light-filled reefs teeming with marine life and  historic wrecks that are accessible to recreational divers, as well as  generally calm and clear conditions.But if you’ve ever visited on an Egyptian liveaboard or while shore diving in Jordan, you’ve probably noticed that the Red Sea doesn’t appear red at all. So how did it get this name and does it ever appear red?