Maria's Day by John Zakour and Scott Roberts for May 17, 2022

It also works for tic-tac-toe!

Never heard the one about “sharp”?

It’s an octothorpe. Everyone knows that.

Hash tags slant forward, and musical sharps slant backward.

Also, octothorpe.

I would say pound sign and octothorpe are in close competition for most archaic name for the symbol.

And this one, “!” is called exclamation point or bang, because BANG!