Insulators are devices installed between conductors at different potentials or between conductors and grounding components, capable of withstanding the effects of voltage and mechanical stresses. There are a wide variety of insulators, each with its unique shape. Although insulators of different types have significantly different structures and shapes, they are both composed of two main parts: the insulating component and the connecting hardware.

Insulators are specialized insulating devices that play a crucial role in overhead transmission lines. In earlier years, insulators were commonly used on utility poles. Over time, they evolved to include many disk-shaped insulators suspended at one end of tall, high-voltage transmission towers. These are intended to increase the creepage distance. Typically made of glass or ceramic, they are referred to as insulators.