Spyware and adware [Wikipedia]
Spyware is computer software that collects personal information about users without their informed consent. The term, coined in 1995 but not widely used for another five years, is often used interchangeably with adware and malware (software designed to infiltrate and damage a computer respectively).
Personal information is secretly recorded with a variety of techniques, including logging keystrokes, recording Internet web browsing history, and scanning documents on the computer's hard disk. Purposes range from overtly criminal (theft of passwords and financial details) to the merely annoying (recording Internet search history for targeted advertising, while consuming computer resources). Spyware may collect different types of information. Some variants attempt to track the web sites a user visits and then send this information to an advertising agency. More malicious variants attempt to intercept passwords or credit card numbers as a user enters them into a web form or other applications.
Phishing web site [Wikipedia]
In computing, phishing is a criminal activity using social engineering techniques. Phishers attempt to fraudulently acquire sensitive information, such as passwords and credit card details, by masquerading as a trustworthy person or business in an electronic communication. Phishing is typically carried out using email or an instant message, although phone contact has been used as well. Attempts to deal with the growing number of reported phishing incidents include legislation, user training, and technical measures.
Malware or malicious software is software designed to infiltrate or damage a computer system without the owner's informed consent. It is a portmanteau of the words "malicious" and "software". The expression is a general term used by computer professionals to mean a variety of forms of hostile, intrusive, or annoying software or program code.
bandwidth consuming protocol
P2P file sharing such as BitTorrent, eDonkey, and Kazaa iMesh. These protocols can consume most of our bandwidth and result in very slow Internet browsing.