A type of program designed to prevent and detect unwanted spyware program installations and to remove those programs if installed

A class of program that searches your hard drive and floppy disks for any known or potential viruses.

Adware, or advertising-supported software, is any software package which automatically plays, displays, or downloads advertisements to a computer. These advertisements can be in the form of a pop-up.[1] The object of the Adware is to generate revenue for its author. Adware, by itself, is harmless; however, some adware may come with integrated spyware such as keyloggers and other privacy-invasive software.

An error in a ‘software’ program. These bugs can cause all sorts of problems with your computer so we really don’t like them. Most bugs are worked out before a program goes live on the Internet but even in the best case scenarios; bugs still happen.

Commercial software is simple software programs developed for commercial use. In most cases you actually purchase it in order to use it. You may have heard of ‘Freeware’ which is software that the public can download onto their computer and use for free. ‘Shareware’ is sort of free and sort of not. Shareware lets you use the software on a trial basis. Thirty days is a normal time frame; after which that you are given the option to purchase it. Some software programs can be downloaded directly to your computer from its website and others prefer to send you the CD’s in the mail. Most companies will offer both ways to choose from.

Crimeware is a class of malware designed specifically to automate cybercrime.[1] The term was coined by Peter Cassidy, Secretary General of the Anti-Phishing Working Group to distinguish it from other kinds of malevolent programs.[citation needed]
Crimeware (as distinct from spyware, adware, and malware) is designed (through social engineering or technical stealth) to perpetrate identity theft in order to access a computer user's online accounts at financial services companies and online retailers for the purpose of taking funds from those accounts or completing unauthorized transactions that enrich the thief controlling the crimeware. Crimeware also often has the intent to export confidential or sensitive information from a network for financial exploitation. Crimeware represents a growing problem in network security as many malicious code threats seek to pilfer confidential information.

A bug in computer lingo is an error of some sort. Programmers do their best to detect and eliminate as many of them as they can before brining a software program to the market. This process is called ‘debugging’ or to ‘debug’.

A non resident computer virus that stores itself in an executable file and infects other files each time the file is run. The majority of all computer viruses are spread when a file is executed or opened. Don't open files attached to emails with a .exe extension. You will regret it

A file is simply a location for stored data. Files can be opened, moved to folders, saved or deleted. They can even be downloaded and uploaded from and to the Internet.

A file extension appears as a suffix which tells you what kind of file it is. For example, if you see a file with a .exe. Warning: be extra careful wehn pening unknown .exe files, they could contain viruses

A firewall is a way to block information from being put on your computer without your knowledge. In other words it is a form of protection for you. A firewall can prevent your computer from obtaining unwanted information from the Internet as well as having precious information removed from your own computer.

Freeware is just like it says…software that is provided at no charge. Be aware that some freeware may contain virusus

Malware, short for malicious software, (sometimes referred to as pestware) is a software designed to secretly access a computer system without the owner's informed consent. 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.
Software is considered to be malware based on the perceived intent of the creator rather than any particular features. Malware includes computer viruses, worms, trojan horses, spyware, dishonest adware, scareware, crimeware, most rootkits, and other malicious and unwanted software or program. In law, malware is sometimes known as a computer contaminant, for instance in the legal codes of several U.S. states, including California and West Virginia.

A rootkit is software that enables continued privileged access to a computer while actively hiding its presence from administrators by subverting standard operating system functionality or other applications. The term rootkit is a concatenation of "root" (the traditional name of the privileged account on Unix operating systems) and the word "kit" (which refers to the software components that implement the tool). The term "rootkit" has negative connotations through its association with malware.[1]
Typically, an attacker installs a rootkit on a computer after first obtaining root-level access, either by exploiting a known vulnerability or by obtaining a password (either by cracking the encryption, or through social engineering). Once a rootkit is installed, it allows an attacker to mask the ongoing intrusion and maintain privileged access to the computer by circumventing normal authentication and authorization mechanisms. Although rootkits can serve a variety of ends, they have gained notoriety primarily as malware, hiding applications that appropriate computing resources or steal passwords without the knowledge of administrators and users of affected systems. Rootkits can target firmware, a hypervisor, the kernel, or—most commonly—user-mode applications.
Rootkit detection is difficult because a rootkit may be able to subvert the software that is intended to find it. Detection methods include using an alternate, trusted operating system; behavioral-based methods; signature scanning; difference scanning; and memory dump analysis. Removal can be complicated or practically impossible, especially in cases where the rootkit resides in the kernel; reinstallation of the operating system may be the only alternative.

Spyware is a type of malware that can be installed on computers, and which collects small pieces of information about users without their knowledge. The presence of spyware is typically hidden from the user, and can be difficult to detect. Typically, spyware is secretly installed on the user's personal computer. Sometimes, however, spywares such as keyloggers are installed by the owner of a shared, corporate, or public computer on purpose in order to secretly monitor other users.
While the term spyware suggests software that secretly monitors the user's computing, the functions of spyware extend well beyond simple monitoring. Spyware programs can collect various types of personal information, such as Internet surfing habits and sites that have been visited, but can also interfere with user control of the computer in other ways, such as installing additional software and redirecting Web browser activity. Spyware is known to change computer settings, resulting in slow connection speeds, different home pages, and/or loss of Internet connection or functionality of other programs. In an attempt to increase the understanding of spyware, a more formal classification of its included software types is provided by the term privacy-invasive software.
In response to the emergence of spyware, a small industry has sprung up dealing in anti-spyware software. Running anti-spyware software has become a widely recognized element of computer security practices for computers, especially those running Microsoft Windows. A number of jurisdictions have passed anti-spyware laws, which usually target any software that is surreptitiously installed to control a user's computer.

A Trojan horse, or Trojan, is software that appears to perform a desirable function for the user prior to run or install, but (perhaps in addition to the expected function) steals information or harms the system. The term is derived from the Trojan Horse story in Greek mythology.

A computer virus is a computer program that can copy itself[1] and infect a computer. The term "virus" is also commonly but erroneously used to refer to other types of malware, including but not limited to adware and spyware programs that do not have the reproductive ability. A true virus can spread from one computer to another (in some form of executable code) when its host is taken to the target computer; for instance because a user sent it over a network or the Internet, or carried it on a removable medium such as a floppy disk, CD, DVD, or USB drive.

A computer worm is a self-replicating malware computer program, which uses a computer network to send copies of itself to other nodes (computers on the network) and it may do so without any user intervention. This is due to security shortcomings on the target computer. Unlike a computer virus, it does not need to attach itself to an existing program. Worms almost always cause at least some harm to the network, even if only by consuming bandwidth, whereas viruses almost always corrupt or modify files on a targeted computer.