[tz] Definition of "timezone"

[Paul Eggert]

On 2023-12-21 12:43, Guy Harris wrote:

> 	https://data.iana.org/time-zones/theory.html
> 
> and it isn't *quite* as explicit as I'd thought:
> 
> 	Each timezone typically corresponds to a geographical region that is smaller than a traditional time zone ...
> 
> Perhaps we should more explicitly state that "timezone" and "time zone" are different names for different things, with a "timezone" *not* corresponding to what most people think of as a "time zone".

I was hoping that the quoted phrase was enough for that, but perhaps 
not. Perhaps italicize or quote "timezone" and "time zone" in it? Or 
some other rewording?


>> The TZDB commentary doesn't use a name for the concept you're asking about, but I suppose "geographical timezone" would do.
> 
> Which concept is that?  ApoY2k said
> 
>> do you (or your
>> peers on the tz project) consider a "timezone" to be inherently tied to the
>> real-world geographical features they are used for, or is the word
>> "timezone" in this context more broader understood as "any 'Zone' entry in
>> the tzdb" - which would e.g. also denote "Etc/UTC" as a "real timezone".
> 
> Are you referring to the first concept - something that is "inherently tied to the real-world geographical features they are used for" - or the second concept, which sounds like a "timezone"?

The former.

> Is the first concept a subset of timezones, restricted to those timezones that have a geographical definition rather than a more abstract definition such as "everything in UTC" for Etc/UTC?

Yes.