I think I'd understand this better if I knew what a boolean gate is.
yes or no for a boolean, or true/false
then these do something to the true/false, ie
not flips it, so true becomes false, false becomes true
or is if one of them is true, then it outputs true, if none are true, it's false
and is if both are true or false, then it's true, if they're different, then it's false