To help you administer SharePoint Online, you can assign one or more users to the SharePoint Online admin role. For a little background, here are each of the administrator roles available in SharePoint Online listed in order of the permissions hierarchy:
- The Global administrator of the Office 365 portal is also a SharePoint Online administrator. When you purchase Office 365, a team site is automatically created, and the Office 365 global admin is included as the primary Site Collection administrator for that site. Keep in mind that you need to assign yourself a SharePoint Online license to access these services or you will receive an “Access Denied” message.
- The SharePoint Online administrator, designated by the Global administrator, has access to the SharePoint Online admin center and can create and manage site collections, designate site collection administrators, manage user profiles, and more. The SharePoint Online admin also needs a SharePoint Online license. See more about this role’s key tasks below.
- The Site collection administrator, which can be designated by the SharePoint Online administrator, has permissions to manage a site collection. A site collection can have several administrators, but only one primary administrator. The SharePoint Online administrator can assign permissions to the primary site collection administrator when creating a site collection, and can add more administrators for the site collection afterwards. Site collection administrators do not have access to the SharePoint Online admin center. They need SharePoint Online licenses to manage site collections.
Note: There is a separate administrator role called the Term store administrator, who can add or change terms in the term store (a directory of common terms you want to use across your organization). To learn more, see Assign roles and permissions to manage term sets.
Key tasks of the SharePoint Online administrator
Reference – https://support.office.com/