Jackson explored a variety of music genres, including pop, soul, rhythm and blues, funk, rock, disco, post-disco, dance-pop and new jack swing. Unlike many artists, Jackson did not write his songs on paper and instead dictated into a sound recorder. In most of his songs, such as "Billie Jean", "Who Is It", and "Tabloid Junkie", he would beatbox and imitate instruments vocally, along with other sounds, instead of playing instruments. Jackson felt it was easier to sing a drum line, or sing a bass, instead of playing a drum line or a bass with an instrument.
According to Steve Huey of AllMusic, Thriller refined the strengths of Off the Wall; the dance and rock tracks were more aggressive, while the pop tunes and ballads were softer and more soulful. Notable tracks included the ballads "The Lady in My Life", "Human Nature" and "The Girl Is Mine"; the funk pieces "Billie Jean" and "Wanna Be Startin' Somethin'"; and the disco set "Baby Be Mine" and "P.Y.T. (Pretty Young Thing)". With Thriller, Christopher Connelly of Rolling Stone commented that Jackson developed his long association with the subliminal theme of paranoia and darker imagery. AllMusic's Stephen Thomas Erlewine noted this is evident on the songs "Billie Jean" and "Wanna Be Startin' Somethin'". In "Billie Jean", Jackson sings about an obsessive fan who alleges he has fathered a child of hers. In "Wanna Be Startin' Somethin'" he argues against gossip and the media. "Beat It" decried gang violence in an homage to West Side Story, and was Jackson's first successful rock cross-over piece, according to Huey. He also observed that the title track "Thriller" began Jackson's interest with the theme of the supernatural, a topic he revisited in subsequent years. In 1985, Jackson co-wrote the charity anthem "We Are the World"; humanitarian themes later became a recurring theme in his lyrics and public persona.
In Bad, Jackson's concept of the predatory lover can be seen on the rock song "Dirty Diana". The lead single "I Just Can't Stop Loving You" is a traditional love ballad, while "Man in the Mirror" is an anthemic ballad of confession and resolution. "Smooth Criminal" was an evocation of bloody assault, rape and likely murder. AllMusic's Stephen Thomas Erlewine states that Dangerous presents Jackson as a very paradoxical individual. He comments the album is more diverse than his previous Bad, as it appeals to an urban audience while also attracting the middle class with anthems like "Heal the World". The first half of the record is dedicated to new jack swing, including songs like "Jam" and "Remember the Time". The album is Jackson's first where social ills become a primary theme; "Why You Wanna Trip on Me", for example, protests against world hunger, AIDS, homelessness and drugs. Dangerous contains sexually charged efforts such as the multifaceted love song, "In the Closet". The title track continues the theme of the predatory lover and compulsive desire. The second half includes introspective, pop-gospel anthems such as "Will You Be There", "Heal the World" and "Keep the Faith"; these songs show Jackson opening up about various personal struggles and worries. In the ballad "Gone Too Soon", Jackson gives tribute to his friend Ryan White and the plight of those with AIDS.
HIStory creates an atmosphere of paranoia. Its content focuses on the hardships and public struggles Jackson went through just prior to its production. In the new jack swing-funk-rock efforts "Scream" and "Tabloid Junkie", along with the R&B ballad "You Are Not Alone", Jackson retaliates against the injustice and isolation he feels, and directs much of his anger at the media. In the introspective ballad "Stranger in Moscow", Jackson laments over his "fall from grace", while songs like "Earth Song", "Childhood", "Little Susie" and "Smile" are all operatic pop pieces. In the track "D.S.", Jackson launched a verbal attack against Tom Sneddon. He describes Sneddon as an antisocial, white supremacist who wanted to "get my ass, dead or alive". Of the song, Sneddon said, "I have not—shall we say—done him the honor of listening to it, but I've been told that it ends with the sound of a gunshot". Invincible found Jackson working heavily with producer Rodney Jerkins. It is a record made up of urban soul like "Cry" and "The Lost Children", ballads such as "Speechless", "Break of Dawn", and "Butterflies" and mixes hip hop, pop, and R&B in "2000 Watts", "Heartbreaker" and "Invincible".
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