The User Account Control is a new security feature of Windows Vista. At this website you will find a typical example of it.
To understand what it does and why it is there, you can take a quick look at the history of the security of Microsoft Windows at the “What is UAC?” section. This website presents the TweakUAC, a free software tool that you can use to quickly turn your UAC or User Account Control of Windows Vista, on or off, or to make UAC operates in the quiet mode. Using this software is extremely easy, all you have to do is download and run it, then select the desired option on its window and press OK. You can learn more about this product and other security services by browsing the sections located at the right hand side of the homepage. These sections are: Pages, Other Resources, Our Software, No Malware, and Any Questions. 
