It's not what they do. It's whether whatever I just added to the regex requires one, the other or both. Or whether what I just deleted cos it didn't work means I should remove, one the other or both. It's just a distraction.
But they are nice pnuemo... newmo... nuemonics ;)
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.