While administrators can manage SharePoint Online through the SharePoint Online Administration Center, they also have the option to perform various tasks through the SharePoint Online Management Shell. This shell is a Windows PowerShell module that administrators can use to manage SharePoint Online users, sites, site collections and organizations.
The principal advantage to using a PowerShell cmdlet is the ability to automate actions using scripts. First, using SharePoint Online PowerShell scripts helps administrators to perform bulk actions. For SharePoint Online, this might include creating hundreds of new SharePoint users -- far too time-consuming to perform individually through the Admin Center. Second, PowerShell scripting brings consistency and reduces errors. For example, a PowerShell script might be the ideal resource for creating new SharePoint Online sites to give a predictable result every time.
Only SharePoint Online global administrators can use the Management Shell, which also requires Windows PowerShell 3.0 or later along with the SharePoint Online Management Shell plug-in from the Microsoft Download Center. Once the services are installed and connected, administrators can create SharePoint Online PowerShell scripts.
SharePoint Online cmdlets follow familiar verb-noun pairings such as Add-SPOUser, Get-SPOUser or Remove-SPOUser to add, see or remove a SharePoint Online user. Similarly, a PowerShell cmdlet such as New-SPOSiteGroup, Get-SPOSiteGroup and Remove-SPOSiteGroup can be used to add, see or remove SharePoint Online groups. In addition to managing users, groups, site collections and organization-level activities, SharePoint Online cmdlets can also be employed to handle service upgrades, service connections and disconnections, and OneDrive synchronizations.
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