Glossary of Virus Related Terms

Antivirus Virus

A virus that looks for and destroys another virus.

Back Door

A program feature, which allows its designer special privileges that are not available to the normal users of the program.

Boot

To start a computer to enable the user to run programs.

Boot Records

Those sections on diskettes or hard disks that contain some of the first instructions executed by a computer when it is booting. Boot records must be loaded and executed in order to load the operating system. Viruses that infect boot records change the boot records to include a copy of themselves. When the computer boots, the virus program is executed and will install itself in memory before the operating system is loaded.

Bug

An error in the design or execution of a program that causes it to do something that was not intended.

Companion virus

A virus that creates a new program with the same file name as an existing program, but in a different place or with a different file type. If the program's name is typed on the command line causes the virus program is activated instead of the original program.

File-infecting virus

Viruses that infect executable files.

Logic Bomb

A computer program that is executed at a specific pre-determined time to cause damage to another computer program or data on your computer

Malicious Code

Any program or piece of code designed to damage a system or to interfere with the manner in which a system was intended to be used.

Master Boot Records

Those boot records on a computer's hard disks that outline the structure of the information on the disk. Each physical hard disk has one master boot record.

Multipartite Virus

A virus that infects both boot records and files.

Rogue Program

Any program that is intend to damage programs or data and includes logic bombs, Trojan Horses and viruses.

Self-Extracting Files

A file which, when executed, decompresses part of itself into one or more new files. Files are usually compressed to conserve disk space and transmission time. An anti-virus program cannot scan compressed files unless the compressed files are first extracted and then scanned.

Self-Garbling Viruses

Viruses whose code is garbled in some way to hide from virus scanning programs.

Stealth Viruses

Viruses which hide from virus scanning programs by hiding themselves in boot records or files.

System Boot Records

Each hard drive has a system boot record associated with it. The system boot record contains code that tells the system about that drive and tables that contain an index to the files on it.

Time Bomb

A logic bomb activated at a certain time or date.

Trojan Horse

A small program that can act like a virus but can't replicate itself. Trojan Horses pretend to be offering you a gift while at the same time containing a malicious hidden agenda.

Virus

A software program designed to replicate and spread on its own and to affect your computer by altering the way it works without your knowledge or permission.

Worm

A program that makes copies of itself elsewhere in a computing system. These copies may be created on the same computer, or may be sent over networks to other computers.

ZIP Files

A compressed file format that requires a decompression utility to decompress such as Winzip.

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