Musically, 7 is the number of notes in the traditional Western major scale. Throughout world music, literature, film and television, as well as in the sports world in many cultures, the number 7 has featured frequently—a sign of how powerfully it appeals to people everywhere and during different eras. Looking at modern communications, 7 is also the number of digits in an American or Canadian telephone number, excluding the area code. We use a 7-day week in the vast majority of today’s world. And many people say they are “in 7th heaven” when they are really happy.