[jesprenj]

It is not null, it's an empty string.

[c0pium]

You should read the referenced RFC, it’s right there.

“””Because all domain names end at the root, which has a null string for a label…”””

[paulddraper]

"null string" or "nil string" or "empty string" are all the same thing.

IDK why we're even talking about this though.