To turn on a specific segment, we connect that pin to the ground or logic low level. In common anode display, the positive pins of all the LEDs are tied together to form the common pin which needs to be provided a ‘HIGH’ signal that means 5 volts signal.
A common pin is also associated with the 7-segment, which is used to identify the type of 7-segment display whether it is the common anode or a common cathode.
