"[1] The term generally applies to popular music, especially rock, R&B, hip hop, dance, and pop.
"[3] Definitions typically include some of the following: that a hook is repetitive, attention-grabbing, memorable, easy to dance to, and has commercial potential and lyrics.
A hook may also garner attention from listeners from other factors, such as the vocal timbre or instrumentation, as in the case of the Beach Boys' use of an Electro-Theremin in "Good Vibrations".
In some studies, radio stations play the hook, typically 8–12 bars long,[6] for audiences of up to 150 participants.
Top 40 stations typically can't wait that long for results and have participants "call out" directly, by listening and rating different hooks.