S.W.A.T. stands for special weapons and tactics.
The New York police department had one of the earliest specially trained police units. In the mid-1880s, the NYPD setup small units of police officers. The department called these units strong arm squads. The squads fought criminal gangs. Police clubs were their only weapons.
An essential piece of equipment is the bulletproof vest, which covers the torso of the officer and is worn either over or under the uniform shirt. Many such vests are made with fibre kevlar, which is capable of stopping most handgun projectiles and many kinds of knifes.
Entry tools such the as battering ram, sledge hammer, and axe are used for forcing open doors.
Dogs were first trained for police work at the turn of the 20th century in Ghent, Belgium, and the practice was soon adopted elsewhere. Although certain breeds with especially keen senses have been used for special purposes- such as detecting caches of illegal drugs and explosive and tracking fugitives and missing persons- the most widely trained dog for regular patrol work is the German Shepherd, or the Alsatian.