The brothers Richard and Maurice McDonald opened the first McDonald's restaurant in 1940 in San Bernardino, California. They introduced the Speedee Service System in 1948 which established the principles of fast food restaurants. Today there are over 37,000 McDonald's restaurants worldwide serving 68 million customers daily. McDonald's predominantly sells hamburgers, chicken, fries, drinks and breakfast items. They have faced criticism over the years concerning nutrition and health but have responded by providing nutritional information and making some changes to their ingredients.