flutter - What is the difference between existing types of snapshots in Firebase?

Question

as I'm further progressing with my code and my coding experiences in Flutter. I've encountered different types of snapshots, while working with the Firebase API. I'm talking about AsyncSnapshots, QuerySnapshots, DocumentSnapshots and DataSnapshots. If there are more pls name them too.

I was wondering, what the exact differences are between those snapshots.

What I've figured so far is that an AsyncSnapshot is probably a Snapshot that is taken asynchronously, meaning the Widget is built before the Data of the Snapshot is available therefore making it async (pls correct me if I'm wrong). Here is where my confussion starts, what exactly is a Snapshot? And what is the "Data" in each of them. For example: Why can't the same function retrieve the needed Data in all of the Snapshots, but is only functioning on a particular Snapshot.

Why is it necessary to convert the Data from a QuerySnapshot to a DocumentSnapshot, to make it accesible (Again pls correct me if I'm wrong)? And what is the exact difference between DocumentSnapshot and DataSnapshot. And why are they called differently, when both of them return Maps?.

Thank you in advance.

Answer 1

Waitting for answers