When did the religions start? : A timeline -- Introduction: Why study the world religions? -- Hinduisms : the world's oldest set of religions -- Judaism : Christianity's mother and older brother -- Buddhism : the West's favorite non-Christian religion -- Confucianism and Daoism : two of the biggest nation's three religions -- Christianity : what you believe but have a hard time explaining -- Shinto : the national religion of Japan -- Islam : the world's most important religion geopolitically -- Two common questions.