A blue moon can refer to the third full moon in a season with four full moons. Most years have twelve full moons that occur approximately monthly. In addition to those twelve full lunar cycles, each solar calendar year contains roughly eleven days more than the lunar year of 12 lunations. The extra days accumulate, so every two or three years (7 times in the 19-year Metonic cycle), there is an extra full moon. Lunisolar calendars have rules about when to insert such an intercalary or embolismic ("leap") month, and what name it is given; e.g. in the Hebrew calendar the month Adar is duplicated. The term "blue moon" comes from folklore. Different traditions and conventions place the extra "blue" full moon at different times in the year.

A "blue moon" is also used colloquially to mean "a rare event", reflected in the phrase "once in a blue moon".

The earliest recorded English usage of the term "blue moon" was in a 1524 pamphlet violently attacking the English clergy, entitled "Rede Me and Be Not Wrothe" ("Read me and be not angry"; or possibly "Counsel Me and Be Not Angry"): "If they say the moon is belewe / We must believe that it is true" [If they say the moon is blue, we must believe that it is true].

Elvis Aaron Presley (January 8, 1935 – August 16, 1977) was one of the most popular American singers of the 20th century. A cultural icon, he is widely known by the single name Elvis. He is often referred to as the "King of Rock and Roll" or simply "the King".

Born in Tupelo, Mississippi, Presley moved to Memphis, Tennessee, with his family at the age of 13. He began his career there in 1954, working with Sun Records owner Sam Phillips, who wanted to bring the sound of African American music to a wider audience. Accompanied by guitarist Scotty Moore and bassist Bill Black, Presley was the most important popularizer of rockabilly, an uptempo, backbeat-driven fusion of country and rhythm and blues. RCA Victor acquired his contract in a deal arranged by Colonel Tom Parker, who would manage the singer for over two decades. Presley's first RCA single, "Heartbreak Hotel", released in January 1956, was a number one hit. He became the leading figure of the newly popular sound of rock and roll with a series of network television appearances and chart-topping records. His energized interpretations of songs, many from African American sources, and his uninhibited performance style made him enormously popular—and controversial. In November 1956, he made his film debut in Love Me Tender.