MOSFET
Beginner
The kind of transistor almost every chip is built from. Its name lists its layers: a metal gate, a thin layer of glass, and silicon underneath.
Novice
Metal–oxide–semiconductor field-effect transistor. The gate sits on a thin insulator above the silicon. Its electric field (no current flows into the gate) controls whether a conducting channel connects the source to the drain.
Expert
A four-terminal device (gate, source, drain, body). Enhancement-mode NMOS and PMOS are the building blocks of CMOS. Planar devices have given way to FinFETs and gate-all-around nanosheets at advanced nodes, but the switch model is the same.