Voltage conversion is the process of changing the voltage level of an electrical signal to meet the requirements of different devices or systems. This is often necessary because various electronic devices operate at different voltage levels. For example, a smartphone may require 5 volts, while a laptop might need 19 volts. To achieve voltage conversion, devices like transformers or voltage regulators are used. Transformers can step up or step down voltage levels in alternating current (AC) systems, while voltage regulators maintain a constant output voltage in direct current (DC) systems. This ensures that devices receive the appropriate voltage for safe and efficient operation.