C#: What is the difference between IAsyncEnumerable and IEnumerable?

IEnumerable — sync iteration. IAsyncEnumerable — async iteration.

IEnumerable:

• Sync.
• foreach.
• In-memory.

IAsyncEnumerable:

• Async.
• await foreach.
• Streaming.

1// IEnumerable
2foreach (var item in GetItems())
3{
4    Console.WriteLine(item);
5}
6
7// IAsyncEnumerable
8await foreach (var item in GetItemsAsync())
9{
10    Console.WriteLine(item);
11}

Key: IAsyncEnumerable for streaming.