Adware

Adware or advertising-supported software is any software package which automatically plays, displays, or downloads advertising material to a computer after the software is installed on it or while the application is being used.

Antivirus Software

Antivirus software consists of computer programs that attempt to identify, thwart and eliminate computer viruses and other malicious software. Antivirus software typically uses two different techniques to accomplish this. The first is examining (scanning) files to look for known viruses matching definitions in a virus dictionary. The second is identifying suspicious behaviour from any computer program which might indicate infection. Such analysis may include data captures, port monitoring and other methods.

Computer Virus

In computer security, a computer virus is a self-replicating computer program that spreads by inserting copies of itself into other executable code or documents. A computer virus behaves in a way similar to a biological virus, which spreads by inserting itself into living cells. The term virus is often extended to refer to worms, trojan horses and other sorts of malware; viruses in the narrow sense of the word are less common than they used to be, compared to other forms of malware.

Firewall

In computing, a firewall is a piece of hardware and/or software which functions in a networked environment to prevent some communications forbidden by the security policy.

Freeware

Freeware is copyrighted computer software which is made available for use free of charge, for an unlimited time, as opposed to shareware where the user is required to pay after some trial period.

Hacker

A hacker is a person who creates and modifies computer software and computer hardware, including computer programming, administration, and security-related items.

Malware

Malware is software designed to infiltrate or damage a computer system, without the owner's informed consent. Malware is commonly taken to include computer viruses, worms, Trojan horses, spyware and some adware.

Spyware

In the field of computing, the term spyware refers to a broad category of malicious software designed to intercept or take partial control of a computer's operation without the informed consent of that machine's owner or legitimate user. While the term taken literally suggests software that surreptitiously monitors the user, it has come to refer more broadly to software that subverts the computer's operation for the benefit of a third party.

Trojan Horse

In the context of computer software, a Trojan horse is a malicious program that is disguised as or embedded within legitimate software. The term is derived from the classical myth of the Trojan Horse. They may look useful or interesting (or at the very least harmless) to an unsuspecting user, but are actually harmful when executed.

Worm

A computer worm is a self-replicating computer program similar to a computer virus. A virus attaches itself to, and becomes part of, another executable program; however, a worm is self-contained and does not need to be part of another program to propagate itself. They are often designed to exploit the file transmission capabilities found on many computers. The main difference between a computer virus and a worm is that a virus cannot propagate by itself whereas worms can. A worm uses a network to send copies of itself to other systems and it does so without any intervention.

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