Pin 0 is digital pin 0
Pin A0 is analog pin 0
It depends on the context - A0 and 0 mean exactly the same thing in the context of analogRead (as is the case here), though they have different numerical values.
Pin 0 is digital pin 0
Pin A0 is analog pin 0
It depends on the context - A0 and 0 mean exactly the same thing in the context of analogRead (as is the case here), though they have different numerical values.