Scalp popping, also known as hair cracking, became a viral sensation on TikTok and Reddit around 2021. The trend involves twisting a small section of hair near the crown of the head and pulling it upward until a loud popping sound is heard, caused by the galea aponeurotica pulling away from the skull. While creators find the sound oddly satisfying, medical professionals have frequently warned against the practice due to risks of internal bleeding or scalp damage. Memes surrounding the trend typically focus on the shocking nature of the sound, the 'addictive' sensation, or the horrified reactions of bystanders who hear the loud crack for the first time.