An Insulated Gate Bipolar Transistor (IGBT) is basically a solid-state electronic switch with no moving parts (like SCRs and Triacs). However, unlike SCR's and Triacs, it can turn OFF as well as ON when current is flowing, and also create a time-controlled transition from OFF to ON or vice versa, when operating in "linear mode".
See Dimmer, IGBT.
See Dimmer, IGBT.