Electrolysis is a permanent hair removal dating back more than 100 years and that has largely been replaced by laser hair removal. Electrolysis is achieved via electrical depilation, which translates to a small metal probe being inserted into a hair follicle, and then electricity is ran through the probe to damage the follicle so it will no longer grow hair. Although it is the only method approved to be called "permanent hair removal" by the FDA, it has become less popular since the 1990s when laser hair removal came on the scene. Because of their differing methods, laser hair removal is much quicker and less painful than electrolysis.