What is an electrical network?  Basically any arrangement of electrical power sources and circuit components is known as electrical network. And electrical power sources can be batteries and generators. Circuit elements are resistance (R), inductance (L), and capacitance (C). 

Bipolar Junction Transistor What is Bipolar Junction Transistor? A bipolar junction transistor is a BJT. A bipolar junction transistor is a three terminal semiconductor device that acts as a static switch or amplifier. And BJT is also called transistor. The name BJT, stands for Transistor, is derived from two words 'transfer' and 'resistor'. Because these two words can describe the operation of a BJT, which is the transfer of a signal from a low-resistance circuit to a high-resistance circuit. Basically a bipolar transistor is a 3 terminal semiconductor device. It consists of two types of semiconductor material, p-type (positive type) and n-type (negative type), and current flows through these regions. Construction of Bipolar Junction Transistor A bipolar junction transistor is formed by sandwiching a p-type or n-type semiconductor between two layers of n-type or p-type semiconductor as shown in the figure. A metal contact is connected to each of the three layers that a