A semiconductor is an element that behaves as a conductor or as an insulator depending on several factors, such as the electric or magnetic field, the pressure, the radiation that affects it, or the temperature at which it is exposed.
In other words, a semiconductor is a material that has an intermediate electrical conductivity between that of metals and insulators.
The most used semiconductor element is silicon and the second is germanium. Semiconductors are widely used in the field of electronics.