Usually, SQL Server and SQL Executive are started and run as Windows NT services. This integration with the Windows NT Service Control Manager allows SQL Server and SQL Executive to be started and stopped as services, either locally or remotely.
Windows NT services run in the security context of a user account that they are assigned. By default, the system assigns the computer's LocalSystem account to services. However, services can have a specifically created Windows NT user account assigned to them.
Before you install SQL Server, you should create a Windows NT user account that can be assigned to the SQL Executive service. This account will enable the service to accomplish connectivity-related tasks, such as performing replication or running scheduled tasks that involve other servers.
During SQL Server installation, the setup program prompts you for the domain, username, and password of a Windows NT user account, which it then assigns to SQL Executive as its user account. (By default, the setup program always assigns SQL Server the LocalSystem account; you can change the account after installation by using the Services application in the Control Panel.) For more information, see Chapter 4, Server Installation.