Common-Emitter (CE) Configuration

What this figure shows. Panel (a) draws the schematic circuit: an NPN transistor with bias source $V_{BE}$ connected between base and the (common) emitter, driving input current $I_B$, and bias source $V_{CE}$ connected between collector and the same common emitter, with output current $I_C$ and the emitter current $I_E$ also marked. Panel (b) redraws the identical circuit with the transistor's standard circuit symbol, showing that here it is the EMITTER (not the base, as in Figure 9.26) that both $V_{BE}$ and $V_{CE}$ share as their common terminal -- this single change of which terminal is common is the entire structural difference between …