You can set them to not visible if you want to. Or you might have some use for them, like I have quote numbers in one of my db that are an autonumber, and I give them out to customers when they call for a price on things. Then I have a button with an inputbox that opens to that exact order. So they are useful even if I don't do anything with them.

From a teaching standpoint, it's a good thing to leave in the video too so you know when he is teaching something how to open a specific record, like open record 4, you can visually see that it's record 4 when it happens. That's a lot more impactful to teaching to see that then to just open a random record and assume it's correct.

But yes, I have 95% of my autonumber fields hidden on forms, if you don't need it just hide it.

You see a lot more uses for it in VBA as well, doing things like concatenation with ID fields, or like Relationships, try teaching Relationships without showing ID fields ;P

Thanks for your thoughts.  I appreciate your inputs.

I find that leaving them visible for teaching purposes gets students used to seeing them. I do show how to hide them eventually.