Boyz II Men, an American R&B singing group, gained popularity in the 1990s for their intricate harmonies and emotional ballads. They have had unprecedented record sales and are considered to be the most successful R&B group of all time. Their phenomenal #1 singles "One Sweet Day" (featuring Mariah Carey), "I'll Make Love to You" and "End of the Road" have broken records for staying for the longest period of time at #1 on the Billboard Hot 100.