Basic objective of this lecture is to presentation on the Bipolar Junction Transistor. Here major focus on Bipolar Junction Transistor’s characteristics and working process. Here discuss all process with explanation and picture. Bipolar junction transistor is a kind of transistor that relies about the contact of two sorts of semiconductor for its functioning. This transistor can be employed as amplifiers, switches, or perhaps in oscillators. This transistor can be located either as individual under the radar components, or in good sized quantities as parts of integrated circuits.