Merge multiple streams into a single one, not taking order into account. If a stream ends before other ones, the other will continue adding data, and the finished one will not add any more data.

Merge multiple streams into a single one, taking order into account, and each stream will wait for a chunk to enqueue before the next stream can append another chunk. If a stream ends before other ones, the other will continue adding data in order, and the finished one will not add any more data.