4 is the fourth studio album by American recording artist Beyoncé Knowles, released through Columbia Records on June 24, 2011. Three weeks before its scheduled release, 4 had leaked onto the Internet. The twelve-song set (eighteen on the deluxe edition) marks the first release by Knowles since separating professionally with father and manager, Mathew, in March 2011. In 2010, Knowles took a break from her career to rest and gain perspective. During the hiatus, Knowles dedicated herself to enjoying the everyday things in life, which she says reignited her creativity and became a source of inspiration. Knowles also drew inspiration from Fela Kuti, Earth, Wind & Fire, Lionel Richie, with additional influences from The Jackson 5, New Edition, Florence and the Machine, Adele, and Prince, among others. Knowles allowed herself the artistic freedom to record songs in which she wanted the melody and lyrics to come together naturally. She mixed the 1970s R&B, the 1990s rock ‘n’ roll as well as her hip hop character and used a lot of horns to create a new and broader sound with musical changes, bridges, vibrata, live instrumentation, and classic songwriting. Knowles' main objective was to bring back the emotion, live instruments and soul music, which according to her, were missing out of the music industry. Allowing herself to belt out some ballads featured on the track-listing of 4 which she described as "a labor of love" Knowles further explained that she used a lot of the brassiness and grittiness in her voice that people had heard in her live performances, however, not necessarily on her studio material. The record is predominately a R&B and pop music album; critics noted a predominant late 1970s and early 1980s R&B and soul music influences. 4 takes on matters of the heart with a mixture of ballads, mid- and up-tempos. For the lyrics, Knowles collaborated a slew of staffwriters. Common themes in the album include womanhood and monogamy. Upon its release, 4 received generally positive reviews from critics, who viewed it as a progression from Knowles' previous albums and commended its mid-tempo musical style, understated production, and her vocal performance. However, some criticized its ballads and songwriting. In the United States, the album debuted at number one on the Billboard 200 chart, selling 310,000 copies in its first week. It also became a number-one chart hit in several other countries. Preceding the album's release, lead single "Run the World (Girls)" was released for digital download worldwide on April 21, 2011. The single was rushed for release after an early demo leaked on April 18, 2011. "Best Thing I Never Had" was released on June 1, 2011, as the album's second single. "Countdown" was released as the third single in the US, it was sent to US mainstream and rhythmic radio on October 4, 2011. "Love on Top" was released as the fourth single in December 2011. "End of Time" was released as the fifth single in the United Kingdom in April 2012.