What is Webcam Blackmail?

Legal Definition
Webcam blackmail is a crime where an online attacker lures victims into taking off their clothes on camera and, usually secretly, allowing them to record a video. The attacker will then make a threat to make the video public unless money is paid. Sometimes threats to make false allegations of paedophilia against the victim are made as well. An increase in webcam blackmails have been reported, and it affects both young and old, male and female alike.
-- Wikipedia