What do you mean by saturation region of transistor?

How do you check if any transistor is properly operating or not?

What is the full form of BJT and tell some application of it.

What is GTO?

A gate turn-off thyristor (GTO) is a special type of thyristor, which is a high-power semiconductor device. It was invented at General Electric. GTOs, as opposed to normal thyristors, are fully controllable switches which can be turned on and off by their third lead, the GATE lead.

What is thyristor ?