"Rapper" is a term that doesn't quite fit Robert Williams, the talented Philadelphia MC who performs as Meek Mill. He is a barker, a bellower – an heir to the tradition of Ice Cube, unloading his rhymes in a rat-a-tat staccato assault, at maximum volume. Listeners who know Meek from his Dreamchasers mixtapes and scene-stealing cameos on Maybach Music compilations will recognize the character in the title track on his major-label debut: a braggart with a chip on his shoulder and a knack for stacking up nifty interior rhymes. ("Did it without an album/I did shit with Mariah/Little nigga, I'm on fire/Icy as a hockey rink, Philly nigga, I'm Flyer.") In hits like the Drake collaboration "Amen," Meek cleverly tweaks sex-rap clichés. But on Dreams and Nightmares he mostly keeps things gritty, telling – that is, yelling – hardscrabble street stories, in a voice big and brassy enough to be heard 20 blocks away.

Listen to 'Dreams and Nightmares'

“Time to Pretend”

Listening to MGMT’s breakthrough song, one might interpret it as being about the excesses of rock stardom, but it’s actually about the duo’s pet praying mantis. Ben Goldwasser and Andrew VanWyngarden told Rolling Stone they got the idea from the insect's jerky movements. The mantis died, but the two bandmates kept the egg sack and allowed the hundreds of eggs to hatch. “We tried to name them all, but they died after a day,” said Goldwasser, with VanWyngarden chiming in, “But the praying mantis dance inspired us.”