A voltage converter is an electrical device that changes the voltage level of an electrical power source. It can either step up (increase) or step down (decrease) the voltage to match the requirements of different devices. For example, a voltage converter can allow a device designed for 110V to operate on a 220V power supply. These converters are essential for ensuring that electronic devices receive the correct voltage for safe and efficient operation. They are commonly used in travel adapters, power supplies, and various industrial applications, helping to prevent damage to equipment and ensuring compatibility across different electrical systems.