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So, let's talk about multitasking within

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PowerShell. While PowerShell is a

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single‑threaded application, it cannot

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start running another command in the same

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console until the first one finishes, and

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you need to make the decision up front to

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move to a long‑running command instead of

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just trying to inject other things into

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the pipeline. Now it's important to

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understand the difference between

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asynchronous and synchronous. For

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asynchronous and synchronous, first off,

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PowerShell runs normal commands

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synchronously, meaning that when you hit

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Return, you then have to wait for that

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command to complete. If you move the job

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into a background job, it allows it to run

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asynchronously, meaning that you can

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continue to use the shell for other tasks

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while that other command completes. When

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we think of synchronous commands, it

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allows you to respond to specific input

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requests. It will produce error messages

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when something goes wrong that you can

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visibly see. It will also display results

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as soon as they become available, so if

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you're querying something, you'll get

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results back. And then, of course, it can

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prompt you for any missing information

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that was required for that command. On the

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flip side of this, when using asynchronous

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commands, you are not allowed to see any

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of the input requests. It can produce

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error messages, but you are often unable

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to see them. It will display results at

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the end of the running task. And there's

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no prompt for any missing information, the

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command itself will just fail. So what are

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the options for multitasking or

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multithreading? Well, the first one here

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is background job, which is what we're

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going to focus on. The second is a

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PowerShell runspace. Now we're not going

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to talk about those too much in this one, we'll just focus on background jobs.