A flagship is a vessel used by the commanding officer of a group of naval ships, characteristically a flag officer entitled by custom to fly a distinguishing flag. Used more loosely, it is the lead ship in a fleet of vessels, typically the first, largest, fastest, most heavily armed, or best known. Over the years, the term "flagship" has become a metaphor used in industries such as broadcasting, automobiles, airlines, and retailing to refer to their highest profile or most expensive products and locations.