What is the 'millennial whoop' and why is it in every pop song?

If you feel like a lot of pop songs these days are starting to sound the same, there's a theory that's taking off on the Internet: they all feature something called "the millennial whoop."

What is "the millennial whoop"?

Coined by The Patterning writer Patrick Metzger, the millennial whoop is "a sequence of notes that alternates between the fifth and third notes of a major scale." Basically, it's that part in California Gurls where Katy Perry starts vocalizing "wa-ohh-wa-ohh" during the bridge (check out 1:05 to see what we mean).

According to Metzger, California Gurls was peak millennial whoop, and since then, nearly every memorable pop song has featured some sequence of "oohs" and "aahs" that aren't far off from Katy's. Carly Rae Jepsen did it in her collaboration with Owl City, Good Time, and Andy Samberg parodied it in his satirical film Popstar: Never Stop Never Stopping.

Quartz summarized how prevalent the whoop is -- noting that it appeared in music industry darling Frank Ocean's Blonde track Ivy -- with an eye-and-ear opening video.

Now you won't be able to get that whoop out of your head.

Can we make it stop?

The commonality of this whoop isn't a bad thing -- patterns and similar melodies have been a staple of music since classical compositions, Metzger says in his essay. "The reason pop music is successful to begin with is because almost every song is immediately familiar before you get more than 10 seconds into a first listen," he says.

And familiar can be comforting. Because sometimes nothing makes you feel better than belting out a good old "wa-ohh-wa-ohh" to whatever song is playing on the radio.