How does Blynk control actual pins on Arduino Nano

I am coming from PIC/MPLAB background so I like to know exactly what is happening on my projects.
Now I can control a Pin (digital pin not virtual) on the Arduino from Blynk without writing any code to control said pin.
So how does it work exactly?

The Blynk library code basically does a DigitalWrite(GPIO,value) to the digital pin when it receives a command from the Blynk server.
If you take a look at files like BlynkApiArduino.h you’ll see how its done.
There are other BlynkApi??? files that do the same thing for alternate systems.

Personally, I don’t like allowing Blynk to control physical pins in this way, and I’d always recommend using virtual pins instead.