A welder joins materials like metals and plastics together using various welding techniques. Welders must wear protective equipment like gloves, jackets, and helmets to shield themselves from heat, flames, and ultraviolet light. Some common welding processes include gas tungsten arc welding, gas metal arc welding, and shielded metal arc welding. For gas metal arc welding specifically, the welder guides the welding gun along the area to be welded, maintaining a consistent distance between the contact tip and workpiece. Proper positioning and orientation of the gun are important for making an accurate weld.