Insulators are categorized by their installation methods, including suspension insulators and pole insulators; by the insulation material used, such as porcelain, glass, and composite (also known as synthetic) insulators; by voltage levels, into low-voltage and high-voltage insulators; and by environmental conditions, into anti-fouling insulators for polluted areas. Different voltage types give rise to DC insulators. Additionally, there are specialized insulators like insulating crossarms, semiconductor glaze insulators, tension insulators for distribution, reel insulators, and wiring insulators, among others. Moreover, they can be divided into two types based on the possibility of insulation breakdown: Type A, non-breakdown, and Type B, breakdown-prone.