Miley Cyrus's raunchy performance at the MTV awards has ignited an online firestorm, prompting calls for heads to roll at the station while leaving others wondering: what exactly is twerking?

The former Disney child star, now 20, took to the stage at the awards ceremony in New York on Sunday night to perform alongside singer Robin Thicke on his song "Blurred Lines."

The 20-year-old, who first pranced around suggestively with a host of giant teddy bears, eventually stripped down to a skin-colored bikini before gyrating in a suggestive manner with a giant foam finger.

Then came the twerking.

With her trademark move of sticking her tongue out, Cyrus bent over and energetically gyrated up against Thicke's crotch.

Described on various Internet sites as the lascivious shaking of the lower extremities with a big assist from the hips, the classic hip-hop move has enjoyed a massive revival in recent years.

Pop star Justin Timberlake -- whose reunion with 'N Sync briefly stole headlines after the MTV awards -- sang in his 2006 hit "SexyBack": "Let me see what ya twerkin' with, look at those hips!"

Cyrus, who twerked away in her video "We Can't Stop," has come under fire for appropriating black culture for her own profit.

In the Huffington Post, entertainment editor Kia Makarechi slammed Miley's "reckless use of black culture as proof that she's subversive and no longer a Disney star."

Actress Brooke Shields, who played Cyrus's mother on the popular kids' show "Hannah Montana," expressed her concern during a turn as a guest host of NBC's Today show.

"I was Hannah Montana's mother. I do not approve," Shields said. "Where did I go wrong? I just want to know who's advising her, and why it's necessary?"

The Parents Television Council (PTC) hit out at MTV for "marketing sexually charged messages to young children using former child stars."

"MTV continues to sexually exploit young women by promoting acts that incorporate 'twerking' in a nude-colored bikini. How is this image of former child star Miley Cyrus appropriate for 14-year-olds?" read a statement from the PTC.

"Heads should roll at MTV," said PTC Advisory Board Member Paul Porter.

Oddly enough, the pop-star's equally famous father Billy Ray Cyrus serves on the PTC board.

The New York Times highlighted the "clumsy white appropriation of black culture," accusing Cyrus of molesting Thicke in a "shambolic, trickster-esque performance."

Heidi Cardenas, a mother of two teenage boys, wrote on CNN's Facebook page that Cyrus was "making a vulgar joke out of her talents and her beauty" and had let down her fans.

However the young songstress -- in 2011 the richest teen in Hollywood -- was unflustered by the hail of criticism, mocking web articles and twerking memes.

She tweeted remarks from Rollling Stone magazine that she had "stolen the night", and posted a few more racy pictures of herself.

"My VMA performance had 306,000 tweets per minute. That's more than the blackout or Superbowl!" she wrote on Twitter.