So, what is the point of Annuals? If a story comes in monthly issue form, and they're numbered as such, how would you know where an annual fits in with the story? If you're buying in real time, you might know "Ok, Issue 64 came out last month, issue 65 comes out in a week, and the annual came out today. Therefore, the annual comes out between 64 and 65."
But what if you're only discovering a series years later? And what would an annual do that they couldn't just cover in the main series?
I'm not much of a comic book guy, but I do like them. I dabble here and there, but it's VERY overwhelming, which is why I stick mostly to batman. At least with batman, they nuke the whole thing every few years, so you can start over, and follow a series through.
With spiderman, it's like "Ok, he's a high school nerd, who has super powers. And the whole series is all canon to each other, and it all fits in a series. But also, Peter Parker has been in high school since the 1940s. But also the world around him ages, and now J Jameson has a podcast, and other modern day reflections are shown in the comic.....but also the series was very much set in modern day 1940s when the series originally began."
THAT'S CONFUSING AS FUCK!!!
And so now, I'm seeing a Harley Quinn series that started in 2021, but there's annuals. I haven't read the series, but.....why do those exist? I don't understand!
There really aren't any rules for Annuals, just think of them as birthday issues for your favorite title.
They CAN be part of the month to month continuity, but they don't have to be.
I've even seen annuals that have their own continuity with other annuals. If it's part of a larger continuity, that will usually be noted on the cover.
For example:
They can be by the same creative team as the monthly book, but again, they don't have to be.
Sometimes annuals serve as try-out books for new writers and artists to see how they handle a property.