Hello and thanks for the help. I have seen -- in formulas and I have no idea
what that means or why the use of a double negative sign. Could someone
please explain to me when this is used and why?

Here's an example of a formula I saw using the --

=SUMPRODUCT(--($A$2:$A$30<""),--(TEXT($A$2:$A$30,"dddd")=$C2),--($B$2:$B$30))

THANKS!