There are numerous services within Windows which transmits information back to Microsoft. Many freeware or paid software many send information back to software supplier. Many of us do not want our privacy information should be transmitted like this.
For e.g Windows Media Player will look to the internet for information regarding song titles and will automatically download codecs when required. It has been reported that it might submit usage information to Microsoft, and will save usage information to your system and much more.
If you want to disable all such spying functionality within your windows then here is freeware tool Xp-AntiSpy. XP-AntiSpy will go deep in to your Windows operating system and enable you to turn off anything that you feel you do not want reported or submitted over the internet.