If an IT person is devoted enough to using the command-line interface for nearly every task they do, they get labeled...
a CLI junkie. While it's powerful, for Office 365 administration, PowerShell is probably not the best option in many cases.
Command-line interface (CLI) junkies eat, sleep and breathe in the command line. Traditionally, Windows administrators -- thanks to the click-and-drag visuals of Windows -- have not been in this camp. However, this changed with Windows PowerShell. PowerShell is user-friendly, with its simple noun-verb syntax and the way you pipe objects directly to other commands. It's an intuitive and easy-to-learn language. You now see Windows CLI junkies joining the ranks of the Linux CLI junkies that have been around for ages. PowerShell expedites many previously mundane tasks and is a great language to learn but people get so caught up in what it can do they try to shoehorn it into whatever task they're doing.
Although PowerShell pays off in situations where an administrator needs to repeat a task, the Office 365 admin center makes Office 365 administration simple for newcomers or for exploring without investing time in a script.
Admin center offers discoverability
When an administrator brings her Office 365 tenant online, she needs to tinker around to discover what features are possible and what they can do. In the Office 365 admin center, everything is nicely laid out in front of you. Users are able to see each component and drill down into each. This visual element allows them to interactively work with the tool and get immediate feedback without having to remember any command-line syntax.
Notice how the various groups are set up, such as users, groups and domains. Admin center displays this navigation bar on the screen at all times, which allows the user to easily drill down into each section and discover where the functionality they want to look into exists.
No prerequisites for Office 365 admin center
The Office 365 admin center is solely based on the browser -- nothing more. You don't need to install any prerequisites to start working with Office 365. To manage Office 365 with PowerShell, you need to install the Microsoft Online Services Sign-In Assistant and the Microsoft Azure Active Directory PowerShell Module ahead of time. When using the admin center, you simply need to point your browser there and go.
Use PowerShell for some one-off tasks
One of PowerShell's claims to fame is how easy it is to automate tasks. One of the main reasons to automate a task is if you plan to do the same task over and over again. Learning how to set up a PowerShell script to create a user is useful if you see a need to create multiple users in the future. You're laying the framework ahead of time to simply specify the user's name and unique attributes.
If you never foresee a time when you'll need automation, you are much better off opening the admin center for user management. If you're bringing up an Office 365 tenant as a proof of concept and need a single user, for example, don't waste your time with the PowerShell script.
Know what PowerShell is and is not
PowerShell allows you to do just about everything around Office 365 management. It is a powerful tool. However, PowerShell requires learning another language. It was built as an automation platform and as a way to manage objects at scale. PowerShell is not an "easier" way to interact with Office 365. Even though I am a Microsoft PowerShell MVP, I admit the Office 365 admin center is intuitive. As someone new to Office 365, I go to the admin center first for routine tasks.
Look to PowerShell when the task will be repeated. Otherwise, stick to the admin center for Office 365 administration.
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