##Nothing but ***A***
Means only ***A***.


##Anything but ***A***
Means that you don't want ***A***. You could have ***B*** or ***C***, or maybe even both ***B*** and ***C*** (and possibly ***E***) - but *NOT* ***A***!


##Everything but ***A***
Means that ***A*** is the only thing you don't want. You do want the rest of the entire alphabet - but *NOT* ***A***!