Subway is the largest fast food chain restaurant in the world, operating in 98 countries. It focuses on serving healthier options like salads and sandwiches. While it faces competition from other large chains like McDonald's and Yum! Brands, Subway distinguishes itself by emphasizing fresh, healthier foods and has partnered with the American Heart Association. Through focusing on building its brand around freshness, Subway has been able to expand globally and attract customers interested in healthier, tasty options.