Look up Background Tasks in the documentation to see how they are supposed to be used.
Think about it: if the task’s result was available right away, it wouldn’t be a background task, would it? The result of creating a task is, therefore, (an object representing) the ongoing task itself.
With this “handle”, you can ask the task how it is progressing, without interrupting the task, or interrupting your browser’s operation. You can ask whether it is done, whether it ended normally, or via an exception.
Not a lot of fancy features, just the essentials, to keep things simple. Very much worth a read.