Chris Brown only shows up once on Rihanna's seventh LP, during the defiant "Nobody's Business." But the abusive ex she took back is like a co-writer throughout, sort of the way Germany was a co-writer on World War II: "I was flying till you knocked me to the floor," she sings on "No Love Allowed." Unapologetic's stark, shadowy R&B is confrontationally honest and sung within an inch of its life, whether she's turning a strip-club anthem into a declaration of independence ("Pour It Out") or pleading at the piano ("Stay"). When she sings, "I'm prepared to die in the moment," on "Love Without Tragedy/Mother Mary," a clichéd line pulses with real terror and impossible resolve. 

Listen to 'Unapologetic'

“Everyday People”

"Everyday People" managed to trailblaze in two different ways -- it was one of the first pop hits to deal with the subject of racial harmony, and it utilized Larry Graham's "slap" technique on the bass guitar, which would soon be copied by countless other bassists. Graham once said about his pulsating style, "I'd never done that before … that's where the freedom of creativity came in for the band, that we'd be allowed to do that." In 1978, the song's line "Different strokes for different folks" would be borrowed for the title of the hit television show Diff'rent Strokes.