The power supply is the most important component of any computer system. It provides the power necessary to run the components of the system. The power supply is responsible for converting the alternating current (AC) from the wall outlet into the direct current (DC) that the computer components need. It also regulates the voltage and current to ensure that the components are not damaged by too much or too little power. The power supply also contains a number of safety features to protect the system from power surges and other electrical problems.