I Want to Hold Your Hand' The Beatles song 'I Want to Hold Your Hand' contains the three letter acronym PSI, which stands for the phrase 'I Love You'. This phrase is a popular expression of affection and has been used in many songs, including the Beatles' hit single. The song was released in 1963 and quickly became one of the most successful singles of all time, reaching number one on the Billboard Hot 100 chart. It has since become an iconic part of the Beatles' legacy and is still widely recognized today.