The default
administrator account that is created during the installation of Windows 7, or setup already for you on a OEM (ex: Dell) computer, will have complete access to the computer and can make any desired changes. To help make the computer more secure, this administrator account may be asked with a
UAC prompt to provide their password or confirmation before allowed to make changes that affect the system, other users, or when running anything elevated (
Run as Administrator) since running elevated will allow it to have access to the entire computer.
The
built-in Administrator account is an account that has full unrestricted access and permission on the computer, and will not be prompted by UAC. It is not recommended to leave the built-in Administrator account always enabled, or use it all the time for just everyday purposes.