As I've said before, it's mostly about semantics.

It depends on how you define "true" how you associate a given voltage level with "true" and "false" and what you mean by NOR, NAND, and NOT.

When I was a pup, we were taught that those "bubbles" on the inputs and outputs of logic components meant to invert the sense of the signal as it passes through the bubble.

If you have a symbol for an AND function, and pass its output through a bubble, it becomes a NAND. If you have an OR function and pass its output through a bubble it becomes a NOR. If you pass its inputs through bubbles, it inverts them before performing its OR function. That OR function is, as always, TRUE when the OR is TRUE. If you pass it through a bubble, it is FALSE, making it a NOR. Therefore, if it takes either of two low inputs and produces a low output for either one, or both, it's a NOR. Physically, it's a 74xx08, but its function is a negative-input NOR, since its inputs are negated (thanks to the bubbles) and it outputs a negated signal (thanks to the output bubble) at its output.

The AND is a negative-logic (if you want to call it that) NOR, because it is an OR with its inputs negated and its output negated. What YOU call it is your choice, and that's why it comes down to a semantic choice. I call it a NOR because that's the function it provides. Physically, it's still a 74xx08.

RE