A reminder and validity and soundness, because yes, in logic, those are two different things.
Validity means an argument checks out symbolically, basically. If it's raining, then I'm president; It's raining, therefore I'm president is valid! It's basic hypothetical syllogism. If A, then B; A, therefore B.
But it is not sound. After all, I am not president, regardless of whether it's raining. To be sound, the parts have to actually add up.