What is the function of the PWR Pin?

Hi,

i am currently examine the code for STM32.
Found out that there is a constant defining a pin

#define PWR_Pin GPIO_PIN_6
#define PWR_GPIO_Port GPIOA

What is the purpose of the PWR Pin?
It is not connected to the Display or should it be used as pwr input ?

I dunno if the IC can handle the current?