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.Baidu is an adware application, which is related to a Chinese search engine. Usually, Adware.Baidu secretly installs itself through browser security exploits or via other unethical mechanisms. Once executed, Adware.Baidu will generate hundreds of annoying popup adverts based on your browsing habits. Adware.Baidu may also connect to the Internet, download, and then install additional malware.
Technical details (How to remove Adware.Baidu(pop up))