If the BE junction voltage of a Triode is greater than 0.7V(except for special Triodes,
such as Darlington), it may be that the BE junction is open.
The first practical device that could amplify was the Triode vacuum tube,
invented in 1906 by Lee De Forest, which led to the first amplifiers around 1912.
TRIAC, from Triode for Alternating Current, is a generalized trade name for an electronic component that can conduct current in either direction when it is triggered,
and is formally called a bidirectional Triode thyristor or bilateral Triode thyristor.