Backdoors: A piece of software that allows access to the computer system bypassing the normal authentication procedures

Dialers: A dialer is a program that either replaces the phone number in a modem's dial-up connection with a long distance number, often out of the country, in order to run up phone charges on a  pay-per-dial numbers, or dials at night to send keylogger or other information to a hacker, running up your phone bill.
 
Exploit: Software that attacks a particular security vulnerability.

Keylogger: Software that copies a computers key strokes to a file, which it may send to a hacker at a later time. Often the keylogger will only "awaken" when a computer connects to a secure website such as a bank. It then logs the keystrokes, which may include account numbers, PIN numbers and passwords, BEFORE they are encrypted by the secure website.

Rootkit: Software inserted into a computer after an attacker has gained control of the system

Spyware: (Adware). This is software that sends information about your internet habits back to the computer from which it is launhed. Spyware is often built into free downloads and works in the background without a user's knowledge.

Trojans: The difference in viruses and trojans is the inability to replicate. Trojans cause damage, unexpected system behavior and compromise the security of systems.

URL Injection: Software that modifies the browser's behavior with respect to some or all domains.

Viruses: A virus can can cause you to have pop-up ads, hijack your browser and change your home page. Cause you to be bombarded with spam. It can make your computer run slow or your can't get on the internet. It also can be a virus of executable code that has the ability to relicate. Biological viruses, computer viruses can spread quickly.

Wabbits:  A type of self-replicating computer program.  Unlike viruses, wabbits do not infect host programs or documents.  They do not use network capabilities of computers to spread.  Instead, a wabbit repeatedly replicates itself on a local computer.  They can be programmed to have (malicious) side effects, in addition to direct consequences of their quick self-replication.  An  example of a wabbit is a fork bomb (also known as logic bomb, code that can be written in one line on any Unix system; used to recursively spawn copies of itself eating all the process table entries and effectively locks up the system).  

 

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