Fear play or terror play is sexual activity involving the use of fear to create sexual arousal. Fear play is typically considered edge play, a category of BDSM related activities with high physical and/or psychological risk. The exact practices vary widely depending the individual participants. Limits are considered very important to follow, however they may be pushed in some edge play scenes to heighten sexual arousal. Asphyxiation is common within edge play sub-sections of BDSM.