The term was created by McAfee because marketing firms objected to having their products called "spyware": in the view of such firms, all the information necessary for informed consent is included in the download agreement. It is widely recognized, however, that many if not most users fail to read a download agreement in sufficient detail to understand exactly what they are downloading. McAfee differentiates PUPs from other types of malware, such as viruses, trojans, and worms, which can be safely assumed to be unwanted by the user.