On this day, April 15, in hip-hop history...

1991: On April 15, 1991, MC Hammer's third album Please Hammer, Don't Hurt 'Em reached diamond status. This was the first rap album in history to become certified diamond.

Armed with the singles "Have You Seen Her" and "U Can't Touch This," Hammer's album quickly became a commercial success after its release in February 1990. It spent 21 weeks at No. 1 on the Billboard 200 and spawned an accompanying film of the same name, in which Hammer returns to his hometown and defeats a local drug lord. Since its release, Hammer's album has become a staple of pop culture, with "U Can't Touch This" being used and parodied in dozens of films and television shows. The phrase "Hammertime" was birthed from this song, and was a very popular term in the early 1990's.

As one of Hammer's biggest hits and one of the songs forever attached to his legacy, "U Can't Touch This," was simple and catchy.  "Thank you for blessin' me/With a mind to rhyme and two hype feet," he rapped. "It feels good, when you know you're down/A super dope homeboy from the Oaktown."

Despite the LP's commercial success, Hammer's pop-rap sensibilities drew extensive criticism from his hip-hop peers. Artists like The D.O.C., Ice Cube, 3rd Bass and the Digital Underground all mocked Hammer's musical style on various projects. Furthermore, many critics panned the album's repetitive lyrics and sound, with Rolling Stone's Michael Corcoran writing that, "he follows a lazy formula, interspersing concern with braggadocio, sexism with black pride."

Still, nothing can take away the LP's place in history.

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