A taser is an electroshock weapon used to incapacitate people allowing them to be approached and handled in an unresisting and thus safe manner. It is sold by Axon, formerly TASER International. It fires two small barbed darts intended to puncture the skin and remain attached to the target, at 55 m/s (120 mph; 200 km/h). Their range extends from 4.5 m (15 ft) for non-Law Enforcement Tasers to 10.5 m (34 ft) for LE Tasers. The darts are connected to the main unit by thin insulated copper wire and deliver a modulated electric current designed to disrupt voluntary control of muscles, causing "neuromuscular incapacitation". The effects of a taser may only be localised pain or strong involuntary long muscle contractions, based on the mode of use and connectivity of the darts.

Tasers are marketed as less-lethal, since the possibility of serious injury or death exists whenever the weapon is deployed. At least 49 people died in the US in 2018 after being shocked by police with a Taser.

The first taser conducted energy weapon was introduced in 1993 as a less-lethal force option for police to use to subdue fleeing, belligerent, or potentially dangerous people, who would have otherwise been subjected to more lethal force options such as firearms. As of 2010, according to one study, over 15,000 law enforcement and military agencies around the world used tasers as part of their use of force continuum.There has been some controversy attending its use on children, and as to whether it constitutes a form of torture.

A 2009 report by the Police Executive Research Forum in the United States found that police officer injuries dropped by 76% in large law enforcement agencies that deployed taser devices in the first decade of the 21st century compared with those that did not use them at all. TASER International and its CEO Rick Smith have claimed that unspecified "police surveys" show that the device has "saved 75,000 lives through 2011".A more recent academic study suggested police use of conducted electrical weapons in the United States was less risky to police officers than hands-on tactics, and showed officer injury rates equal to use of chemical sprays such as oleoresin capsicum. However, when police combined conducted electrical weapons with use of other weapons, officers were four or five times more likely to be injured than when using a baton or chemical spray.