The Windows Local Administrator Account is a Windows Default Local Account.
Administrator account
The default local Administrator account is a user account for the system administrator. Every computer has an Administrator account (SID S-1-5-domain-500, display name Administrator). The Administrator account is the first account that is created during the Windows installation.
The Administrator account has full control of the files, directories, services, and other resources on the local computer. The Administrator account can create other local users, assign user rights, and assign permissions. The Administrator account can take control of local resources at any time simply by changing the user rights and permissions.
The default Administrator account cannot be deleted or locked out, but it can be renamed or disabled.
In Windows 10 and Windows Server 2016, Windows setup disables the built-in Administrator account and creates another local account that is a member of the Administrators group. Members of the Administrators groups can run apps with elevated permissions without using the Run as Administrator option. Fast User Switching is more secure than using Runas or different-user elevation.
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Important Even when the Administrator account has been disabled, it can still be used to gain access to a computer by using safe mode. In the Recovery Console or in safe mode, the Administrator account is automatically enabled. When normal operations are resumed, it is disabled.
