Kendrick Lamar: is amazing because he has like 50 different flows, his lyrics are brilliant/meaningful, beats are dope, and he can spit hot fire. His album good Kid, M.A.A.D City is fucking sexyyyyyyyyyyyy. Listen to it from start to finish. Section 80 is also rad, but I like all of his music really.
Jurassic 5: is an older hip hop collective with completely clean lyrics. They are some of the most talented rappers out there. Feedback is my favorite album, but they all are pretty good.
OutKast: because OutKast, you've probably listened to a lot of that already if you like hiphop.
Atmosphere: has some fantastic lyrics. When Life Gives You Lemons, You Paint That Shit Gold is a groovy album, but again, all of his work is pretty good.
Childish Gambino: one of my favorite rappers out there. Lyrically he's on another level. Camp, Royalty, Culdesac, Because the Internet are his 4 LPs and they are all fantastic. Camp is my favorite though, I love every song on that album.
Hieroglyphics/Souls of Mischief: Souls of Mischief is just a sub group of Hieroglyphics so I'm mentioning them in the same paragraph. They are pretty sweet, Full Circle is a good Hiero album and '93 till Infinity is a siiiick Souls of Mischief album.
The Underachievers are worth a mention.
I have much more if you'd like.