A tourniquet is a medical device used to control bleeding by applying pressure to a limb. It is typically a band or strap that can be tightened around an arm or leg to restrict blood flow. Tourniquets are often used in emergency situations, such as traumatic injuries, to prevent excessive blood loss until professional medical help is available. In addition to their use in emergencies, tourniquets are also employed in surgical settings to create a bloodless field. They are an essential tool for first responders and are included in many first aid kits. Proper application and removal are crucial to avoid complications, such as tissue damage.