In the completed transistor, n-type silicon has been embedded in p-type silicon by doping, after which the non-conductor (isolator) and conductor are incorporated.
If electric current runs through this circuit, electrons gather through electrostatic induction in the area of the p-type silicon opposite the conductor, enabling current to pass between the n-type silicon points. The way in which the p-type silicon is affected by the electric field of the conductor, despite its being isolated by the non-conductor, is referred to as field effect.

This transistor works by switching the current on and off.

This kind of transistor, in which a non-conductor (isolator) and metal conductor are placed on top of a semiconductor, is known as an MOS (Metal Oxide Semiconductor), and an MOS that makes use of field effect is further known as an MOS FET.