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Welcome back! In this module, we'll take a look at how PowerShell works

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with objects in the pipeline and why it matters to you.

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Understanding this paradigm is crucial to your success in using

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and eventually scripting with PowerShell.

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This is something that can be difficult for PowerShell

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beginners to truly grasp, but once they do,

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a lot of things begin to make sense.

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PowerShell is all about working with objects in a pipeline.

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You're not parsing a bunch of text to get results to look the way you want them.

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You're telling PowerShell, get me these things,

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do something with them, and then finally, show me the results.

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PowerShell is an interactive management tool that takes advantage of this

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pipeline process. And it doesn't matter if you're running PowerShell

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interactively, at a console prompt as we're doing in this course,

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or running PowerShell in a script or function,

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it's still all about objects in the pipeline.

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Traditional and legacy tools tend to be text based. Even something

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like VBScript that sort of gives you objects, you still often

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needed to treat those results like text in order to get the

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desired output. With these tools,

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and you can think of command line tools like netstat or

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Linux commands like ps, they give you text,

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which you often have to parse to get exactly what you want.

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Now, this is not necessarily a bad thing.

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Linux has terrific tools for this task like grep and awk,

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assuming you know how to use them.

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But Windows is not text based, right?

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It's based on objects, and to a great extent this means .NET.

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So it makes sense that a management tool for Windows would

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be based on .NET and be object centered.

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Now,

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because of this dependency on .NET, Windows PowerShell

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remained a proprietary language.

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But, once Microsoft decided to make .NET Core available on

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non‑Windows platforms and made it an open source project,

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PowerShell really wasn't that far behind.

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And really, that's where we are today.

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The version of PowerShell that runs on Windows,

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Linux, and Mac is relying on .NET Core. And even on non‑Windows

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platforms, the concept is still objects in the pipeline.

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When you run a PowerShell command,

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it's typically creating and, in some situations,

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consuming objects.

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This is really what the pipeline is all about.

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You get a bunch of things in PowerShell and pass them to

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another command and then on to another.

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Where it gets tricky is that you may start with one type of object

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and end up with something completely different,

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depending on what the cmdlet you are piping to is designed to do.

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Now this is actually a good thing because it means you can

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perform some pretty complex commands from a PowerShell prompt

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with no scripting and minimal effort.

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At the end of your pipeline expression,

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PowerShell displays whatever is left in the pipeline to your screen.

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But up until that point, it's really all about objects in the pipeline.

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Of course, it helps to understand what an object means in this context.

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You don't have to be a developer to use PowerShell,

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but you should understand a few basic concepts.

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Now for our purposes,

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an object is a software representation of some thing

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that you want to manage or work with.

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It could be a process, service, mailbox, or vegetable. Objects have

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properties, which are ways to describe it. Thinking about our vegetable, it

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might have a property to control or show the color.

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Maybe there's a property that gives you the number of

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objects or number of vegetables.

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The other common part of an object is this idea of methods.

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These are actions that you can do to an object or maybe that the object does.

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Continuing with our vegetable object idea,

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it might have methods of, say, peel or chop.

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Now don't worry, most of the time you'll use cmdlets to manipulate objects,

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even though under the hood these cmdlets are working with the

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properties and methods of the corresponding objects.

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Now you can too, and sometimes you really have no choice.

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But for now, as a beginner, you should be able to use,

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and you should stick with using PowerShell cmdlets.

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There are other elements to an object,

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but properties and methods are the primary ones that we'll be focusing on. These are referred to generically, or collectively, as an object's members.