Double.TryParse(InputValue,0) explanation

I am unable to understand what that (0) stands for within double.TryParse brackets.
This is from academy

Thank you in advance

@Vidya_Srinivasan - its a signature of the
Double.TryParse(input string , output double).

pls refer below link


This doesn’t answer it for me. Perhaps you can elaborate. The .NET link you provided specifies that the second argument (double) TryParse(String, Double) has to be variable and gives out an error when set to 0.