Final answer:
Insulators are materials that inhibit the movement of electrical or thermal energy, maintaining charge and preventing heat transfer. Materials like plastic and wood are typical examples, while semi-conductors like silicon can act as insulators or conductors depending on the temperature.
Step-by-step explanation:
An insulator is a material that significantly impedes the transfer of electrical or thermal energy. Common examples of insulators include plastic and wood. These materials do not allow charges to move through them freely because electrons and ions are tightly bound within the structure, moving as much as 1023 times more slowly compared to conductors. In contrast to conductors, where loose electrons enable easy energy transfer, insulators retain any added charge because it cannot flow freely.
Insulating materials are used in various applications to prevent unwanted heat loss or gain, as they limit the conduction of heat from one area to another. In the context of electricity, insulating materials like glass, ceramic, and certain types of rubber help in safely handling and directing the flow of current in electrical applications, preventing shorts and protecting users from electric shocks.
Some materials exhibit properties of both insulators and conductors, known as semi-conductors. Elements like silicon and germanium function as insulators at low temperatures but can conduct electricity at higher temperatures. This unique trait is key in the manufacturing of electronic components.