Windows Vista User Account Control (UAC)

Microsoft's continuing focus on security has taken great strides in the development of the User Account Control in Windows Vista. This new feature is very helpful to both business and home users. It gives greater flexibility for a standard user while maintaining the integrity of the operating system. By default, standard user permissions in Windows Vista are as
follows:
*View system clock and calendar
* Change time zone
*Install Wired Equivalent Privacy (WEP) to connect to secure wireless networks
*Change power management settings
* Add printers and other devices that have the required drivers installed on computer or have been allowed by
an IT administrator in Group Policy
* Install ActiveX Controls from sites approved by an IT
administrator
*Create and configure a Virtual Private Network connection l Install critical Windows Updates In addition, since the disk defragmentation task is now Automated by default, standard users will no longer have the need to invoke this tool. As you can see from the permissions list, there isn't anything a standard user can do to change the configuration of the system nor is there any chance that a standard user can accidentally download a virus. For even greater flexibility, system administrators have the ability to remove any of the preset permissions that they see fit from a standard users account.

The UAC feature was created to help IT Administrators keep standard users productive while keeping the network available