Rap for the club. Always confused when people call it hiphop (when hip hop is a culture, and hip hop music is rap). Commercial rap is also used as the single or main promotion song for an artist's album.
Snap Yo Fingers is like the best commercial rap song out!
Rap that is played at school dances, in the club, and is liked by white preps that think they are soo hood. Used for grinding and all that shit. Played during halftime at a boys basketball game.
Commercial rap: 50 Cent, Soulja Boy, Baby Bash, etc.
Real rap: Snoop Dogg, Method Man, Redman, Run DMC, Will Smith, Notorious B.I.G , etc.
Rap music in today's culture that is basically a repeat of the same song type. -Commonly "gangster rap" Most songs talk about getting money, gang banging, and some form of an explicit love song. The style is the same in music using heavy bass lines and hard drum machines. Often people will mistake it as real hip-hop or think the artist is cool for using elementary metaphors. Generally it is the opposite of underground rap.
2. Most likely your favorite artist (if he/or she is on the radio a lot)
3. "Why don't you listen to a lot of lil wayne?" "Half the time, the song styles don't change. It's the same thing everytime, new beats, new rhyme, same subject; aka Commercial Rap"