The codenames for every major Debian release are named after characters from Pixar's Toy Story franchise. Debian's unstable release is fittingly named after Sid, an unstable character from the Toy Story movies.
And if they ever run out of Toy Story characters, the Marvel universe has thousands of other characters...
Not to mention other Pixar film characters.
Especially when you realise main releases happen every five years, or so
That's what I thought. I think the most popular name they have actually used is Jessie.
unfortunately there's no rhyme or reason to the naming. which came first: bookworm, buster, or bullseye? They should just use numbers.
Numbers give the wrong impression that one version follows another. Debian release channels exit alongside each other individually. Giving the release channels names helps to make that distinction. It also makes for an easy layout of packages in APT repositories.
Sid is and always has been Sid. If you were to assign numbers, what number should replace that name? There are perfectly working labels for release channels and there is no reasonable replacement.
R releases all have code names that are Peanuts references, like "Bunny Wunnies Freak Out".
I ran Sid for years, I knew what it was named for and that was cool.
Lately though I have been wondering if they are going to run out of characters? Maybe it's time to latch onto something else? I don't know..