Inferred Types

With variable declarations, you can use var to let Java figure out the type of the variable.

var name = "Jupiter";

This is not allowed with argument declarations.

// You aren't allowed to use var for arguments!
void makeHorchata(var milkFatPercent) {
    // ...
}

You must always explicitly write out the types of arguments.

void makeHorchata(double milkFatPercent) {
    System.out.println(
        "Making a horchata with " + milkFatPercent + "% milk."
    );
}