A taser is an electroshock weapon sold by Taser International. It uses electrical current to disrupt voluntary control of muscles causing "neuromuscular incapacitation". Someone struck by a Taser experiences stimulation of his or her sensory nerves and motor nerves, resulting in strong involuntary muscle contractions. Tasers do not rely only on pain compliance, except when used in Drive Stun mode, and are thus preferred by some law enforcement over non-Taser stun guns and other electronic control weapons. There are two main police models, the M26 and X26. Both come with accessories including a laser sight and optional mounted digital video camera that can record in low-light situations. Taser International sells a civilian model called the C2. On 27 July 2009, Taser introduced the X3, capable of firing three times without reload.
Tasers were introduced as non-lethal weapons to be used by police to subdue fleeing, belligerent, or potentially dangerous people, who would have otherwise been subjected to more lethal weapons such as a firearm. A 2009 Police Executive Research Forum study said that officer injuries drop by 76% when a Taser is used. However, while Taser CEO Rick Smith has stated that police surveys show that the device has saved 75,000 lives, there has been some controversy over several incidents where Taser was implicated in instances of serious injury or death.

en.wikipedia.org/wiki/Taser