What is component 8 in figure T-2?

Component 8 in Figure T-2 is the schematic symbol for a Light Emitting Diode, commonly known as an LED. The base of the symbol is a standard diode—a triangle pressing against a straight line—indicating that current can only flow in one specific direction. The unique feature that identifies it specifically as an LED is the pair of small arrows pointing away from the triangle. These outward-pointing arrows represent light radiating out into the environment. If the arrows were pointing inward, it would represent a photodiode, which detects light instead of emitting it.