Adware:Adware (or spyware) is a small program that is designed to show advertisements (in various form and degrees of intrusiveness) on your computer. It often reports personal information back to its owners. As a result your sense of privacy can be violated.
Adware.Desktop is an adware tool that may gain access to your computer through email attachments or browser security holes, and even instant messengers and file sharing programs. Adware.Desktop may monitor your browser habits and report this information to a third party user, which may lead to identity theft.
Technical details (How to remove Adware.Desktop(pop up))