A semiconductor device is an electronic component made from a material such as silicon that has the ability to conduct electricity under certain conditions. The two most common types of semiconductor devices are transistors and diodes. A transistor is a three-terminal device that can be used to amplify or switch electrical signals and power. A DIODE is a two-terminal device that allows current to flow in one direction only. Both transistors and diodes are widely used in modern electronics and are essential components in many electronic circuits.