Grayware
Grayware (or greyware) is a general term that refers to applications or files that are not directly classified as malware (like worms or trojan horses), but can still negatively affect the performance of computers and involve significant security risks.
It describes applications that behave in an annoying or undesirable manner, and yet are less serious or troublesome than malware. Grayware encompasses spyware, adware, dialers, joke programs, remote access tools and any other program apart from a virus, that is designed to harm the performance of computers. The term is in use since around 2004.
Another term is PUP which stands for Potentially Unwanted Program. Applications unwanted despite have been downloaded by the user, users may fail to read a download agreement. PUPs include spyware, adware, and dialers.
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