1) Plain, generic, commercial "hard rock" that is safe for radio play and appeals to a wider, more tame audience. It does not really adhere to the spirit of rock'n'roll. It seems more like a money making ploy than about the art, emotion, or rebellion. Rock that parents would approve of.
2) Nickelback, Breaking Benjamin, Three Days Grace, etc.
"Get off the stage, this gener-rock blows."
-anyone who accidentally found themselves at a nickelback concert
"I can't believe he plays bass in that poppy emo band. In reality, he's into Phish. That doesn't make any sense. He's probably just in it for the money."
-about a soulless musician in a gener-rock band