Quick helpful glossary
This glossary lists some of the most commonly used terms you may come across when reading about online security and privacy threats.
There are however many terms, abbreviations and acronyms surrounding computers and Internet security. If there is another term you do not recognise that is not on our list, or you are seeking more advanced information you might like to try our McAfee Threat Centre glossary, which contains a far more detailed and comprehensive list, simply click here to access our Threat Centre Glossary
Adware
Adware is a legitimate, non-replicating program designed to display ads to the end-user, often based on monitoring of browsing habits, and often in exchange for the right to use a program without paying for it (a take on the shareware concept).
Anti-antivirus Virus
Anti-antivirus viruses attack, disable or infect specific anti-virus software.
Anti-virus Software
Anti-virus software scans a computer's memory and disk drives for viruses. If it finds a virus, the application informs the user and may clean, delete or quarantine any files, directories or disks affected by the malicious code. Also see: Anti-virus Scanner
Anti-virus Virus
Anti-virus viruses specifically look for and remove other viruses.
Attack
An attack is an attempt to subvert or bypass a system's security. Attacks may be passive or active. Active attacks attempt to alter or destroy data. Passive attacks try to intercept or read data without changing it.
Back Door
A back door is a feature programmers often build into programs to allow special privileges normally denied to users of the program. Often programmers build back doors so they can fix bugs. If hackers or others learn about a back door, the feature may pose a security risk. This is also called a trap door.
Backup
n. A backup is a duplicate copy of data made for archiving purposes or for protection against damage and loss.
v. A backup is also the process of creating duplicate data. Some programs back up data files while maintaining both the current version and the preceding version on disk. However, a backup is not considered secure unless it is stored in a location separate from the original.
Blog
A blog is a web site where users regularly post up-to-date journal entries of their thoughts on any subject they choose. It is readable by anyone on the Web. Derived from the term Web Log. Bluetooth or IEEE 802.15.1 Named after 10th century Danish King, Harald Blatan (Bluetooth), who was known as a uniter: It is a set of wireless standards for short-range communication between wireless headsets, phones, PDAs, keyboards, and other devices.
Boot
To boot a computer is to start (a cold boot) or reset (warm boot) the system so it is ready to run programs for the user. Booting the computer executes various programs to check and prepare the computer for use. Bot This term refers to a program that automatically searches for and retries information or generates generic traffic over the network. They are often used for legitimate purposes such as by search engines, instant message (IM) programs, and other Internet services. They can be used to take control of computers or launch attacks.
Browser Hijacker
A browser hijacker is a type of spyware that allows the hacker to spy on the infected PC’s browsing activity, to deliver pop-up ads, to reset the browser homepage, and to redirect the browser to other unexpected sites. Also see: Spyware
Bug
A bug is an unintentional fault in a program that causes actions that neither the user nor the program author intended.
Chat room
An online forum where individuals or groups can exchange comments in real time. Some chat rooms have moderators who can control behavour and access. Some chat rooms allow anonymity which has been known to allow sexual predators to target unsuspecting children.
Companion Virus
Companion viruses use a feature of DOS that allows software programs with the same name, but with different extensions, to operate with different priorities.Often the virus will execute the original program afterwards so the system appears normal.
Cookie
Cookies are small text files that many Web sites use to store information about pages visited and other settings (temporary or persistent). For example, cookies might contain login or registration information, shopping cart information, or user preferences. When a server receives a browser request that includes a cookie, the server can use the information stored in the cookie to customize the Web site for the user.
Crimeware
Crimeware is malicious software such as viruses, Trojan horses, spyware, deceptive scripts, and other programs used to commit crimes on the Internet including identity theft and fraud. Also see: Malware
Denial of Service (DoS)
A denial of service attack (DoS) is an attack specifically designed to prevent the normal functioning of a system and thereby to prevent lawful access to the system by authorized users. Hackers can cause denial of service attacks by destroying or modifying data or by overloading the system's servers until service to authorized users is delayed or prevented.
Dialer
Software that redirects Internet connections to a party other than the user's default ISP to run up additional connection charges for a content provider, vendor, or other third party.
EXE File
An EXE is an executable file. Usually, it is executed by double-clicking its icon or a shortcut on the desktop, or by entering the name of the program at a command prompt. Executable files can also be executed from other programs. The vast majority of known viruses infect executable files. This is also called a program file.
False Negative
A false negative error occurs when anti-virus software fails to indicate that an infected file is truly infected. False negatives are more serious than false positives, although both are undesirable. False negatives are more common with anti-virus software because the may miss a new or a heavily modified virus. Also see: False Positive
False Positive
A false positive error occurs when anti-virus software wrongly claims that a virus is infecting a clean file. False positives usually occur when the string chosen for a given virus signature is also present in another program. Also see: False Negative
Firewall
A firewall prevents computers on a network from communicating directly with external computer systems. A firewall typically consists of a computer that acts as a barrier through which all information passing between the networks and the external systems must travel. The firewall software analyzes information passing between the two and rejects it if it does not conform to pre-configured rules.
Hacker
A hacker is a person who creates and modifies computer software and hardware, including computer programming, administration, and security-related items. This can be done for either negative or positive reasons. Criminal hackers create malware in order to commit crimes. Also see: Malware.
Hijacking
Hijacking is an attack whereby an active, established, session is intercepted and used by the attacker. Hijacking can occur locally if, for example, a legitimate user leaves a computer unprotected. Remote hijacking can occur via the Internet.
Host
Host is a term often used to describe the computer file to which a virus attaches itself. Most viruses run when the computer or user tries to execute the host file.
Instant Messenger
A program that allows two or more people to communicate with one another over the Internet in real time. Some services also allow the user to share files.
Infection
Infection is the action a virus carries out when it enters a computer system or storage device.
ISP
ISP stands for Internet Service Provider. ISPs are companies that provide users access to the Internet for a monthly fee.
Keylogger
Keyloggers are malicious programs that record the key strokes a user types on their PC, including instant message and email text, email addresses and websites visited, passwords, credit card and account numbers, addresses, and other private data.
Mail Bomb
A mail bomb is an excessively large e-mail (typically many thousands of messages) or one large message sent to a user's e-mail account. This is done to crash the system and prevent genuine messages from being received.
Malicious Code
Malicious code is a piece of code designed to damage a system and the data it contains, or to prevent the system from being used in its normal manner.
Malware
Malware is a generic term used to describe malicious software such as viruses, Trojan horses, spyware, and malicious active content.
MP3 File
MP3 files are Moving Picture Experts Group Audio Layer 3 files. They are highly compressed audio tracks, and are very popular on the Internet. MP3 files are not programs, and viruses cannot infect them. This file type has the extension MP3.
MS-DOS
MS-DOS is the Microsoft Disk Operating System. Microsoft developed this operating system for the IBM platform before Windows. Windows operating systems rely heavily on MS-DOS and can execute most MS-DOS commands.
Newsgroup
A newsgroup is an electronic forum where readers post articles and follow-up messages on a specified topic. An Internet newsgroup allows people from around the world discuss common interests. Each newsgroup name indicates the newsgroup's subject in terms of increasingly narrow categories, such as alt.comp.virus.
Operating System
The operating system (OS) is the underlying software that enables you to interact with the computer. The operating system controls computer storage, communications and task management functions. Examples of common operating stems are MS-DOS, MacOS, Linux, and Windows 98.
Password Attacks
A password attack is an attempt to obtain or decrypt a legitimate user's password. Hackers can use password dictionaries, cracking programs, and password sniffers in password attacks. Defense against password attacks is rather limited but usually consists of a password policy including a minimum length, unrecognizable words, and frequent changes.
PDA
Short for "Personal Digital Assistant." A hand-held device that combines computing, telephone/fax, Internet and networking features.
Peer-to-Peer Networking (P2P)
Peer-to-Peer networking (P2P) is a distributed system of file sharing where any PC on the network can see any other PC on the network. Users access each others’ hard drives to download files. This type of file sharing is valuable, but it brings up copyright issues for music, movies, and other shared media files. Users are also vulnerable to viruses, Trojans, and spyware hiding in files. Also see: Trojan Horse, Spyware
Pharming
Pharming is the exploitation of a vulnerability in DNS server software that allows a hacker to redirect a legitimate web site's traffic to a counterfeit web site. The spoofed site is designed to steal personal information such as usernames, passwords, and account information.
Phishing
Phishing is a form of criminal activity using social engineering techniques through email or instant messaging. Phishers attempt to fraudulently acquire other people’s personal information, such as passwords and credit card details, by masquerading as a trustworthy person or business in an apparently official electronic communication.
Ransomware
Ransomware is malicious software that encrypts the hard drive of the PC that it infects. The hacker then extorts money from the PC’s owner in exchange for decryption software to make the PC’s data usable again.
RSS
Really Simple Syndication: an XML format used to create web feeds of content available on news sites, blogs, and other Web sites with fast-changing information. The feeds can contain headlines and summaries of content, and subscribers use RSS readers to view them.
Shareware
Shareware is software distributed for evaluation without cost, but that requires payment to the author for full rights. If, after trying the software, you do not intend to use it, you simply delete it. Using unregistered shareware beyond the evaluation period is pirating.
Spam
Spam is unsolicited or undesired bulk electronic messages. There is e-mail spam, instant messaging spam, Usenet newsgroup spam, Web search engine spam, spam in blogs, and mobile phone messaging spam. Spam includes legitimate advertisements, misleading advertisements, and phishing messages designed to trick recipients into giving up personal and financial information.
Spam Filter
A spam filter is a program used to detect unsolicited e-mail to prevent spam from making it to a user's inbox. Filters use heuristics, keyword scans, whitelists and blacklists, and other processes. The filters are placed on email and ISP servers, in anti-spam software, and in anti-phishing browsers.
Spyware
Spyware is a wide range of unwanted programs that exploit infected computers for commercial gain. They can deliver unsolicited pop-up advertisements, steal personal information (including financial information such as credit card numbers), monitor Web-browsing activity for marketing purposes, or route HTTP requests to advertising sites.
Trojan Horse
A Trojan horse is a malicious program that pretends to be a benign application. It purposefully does something the user does not expect. Trojans are not viruses since they do not replicate, but they can be just as destructive.
Virus
A virus is a computer program file capable of attaching to disks or other files and replicating itself repeatedly, typically without user knowledge or permission. Some viruses attach to files so when the infected file executes, the virus also executes. Other viruses sit in a computer's memory and infect files as the computer opens, modifies or creates the files. Some viruses display symptoms, and others damage files and computer systems, but neither is essential in the definition of a virus; a non-damaging virus is still a virus.
There are computer viruses written for several operating systems including DOS, Windows, Amiga, Macintosh, Atari, UNIX, and others. McAfee.com presently detects more than 57,000 viruses, Trojans, and other malicious software.
Virus Hoaxes
Virus hoaxes are not viruses, but are usually e-mails warning people about a virus or other malicious software program. Some hoaxes cause as much trouble as viruses by causing massive amounts of unnecessary e-mail. Most hoaxes contain one or more of the following characteristics:
- Warnings about alleged new viruses and their damaging consequences,
- Demands the reader forward the warning to as many people as possible,
- Pseudo-technical "information" describing the virus,
- Bogus comments from officials: FBI, software companies, news agencies, etc.
- Sometimes hoaxes start out as viruses and some viruses start as hoaxes, so both viruses and virus hoaxes should be considered a threat.
VoIP
Voice over Internet Protocol a digital facility that voice transmissions over the Internet or other IP networks. Skype is an example of a VOIP Service.
Worm
Worms are parasitic computer programs that replicate, but unlike viruses, do not infect other computer program files. Worms can create copies on the same computer, or can send the copies to other computers via a network. Worms often spread via IRC (Internet Relay Chat).
