Viruses, Worms and Trojans - What is the Difference and How to Protect Yourself From Them

Anyone who uses a computer has undoubtedly heardattached to a file, and the file has to be opened before
the terms "computer virus", "worm", and "Trojan". Mostinfection can take place. Unlike a virus, that is passed
use these terms interchangeably to describe a virus.from computer to computer via user action; worms
What you may not realize though, is that computerare designed to self-replicate and spread without any
worms and Trojan horses are not computer viruses ateffort on the user's part. When you open a file that
all.contains a worm, it starts spreading through networks
While each of these three computer security threatsand emails immediately. The main purpose of a worm
shares some common characteristics, there are someattack is to bring down systems and networks by
distinct differences between viruses, worms, andconsuming great amounts of bandwidth and memory.
Trojans that cause them to stand on their own as aWorms are also used as a means for a remote
category of malicious software. The main similarity isattacker to tunnel into your system. Many worms will
that all are bad, and can potentially cause you, yourreplicate themselves by sending "clones" to everyone
computer, or your network a great deal of harm.in your email address book. These emails are sent out
Common Characteristics of Viruses, Worms, andimmediately upon opening the infected file.
TrojansA Trojan Horse is also included in a file, and like a virus,
All computer viruses, worms, and Trojan horses aredoes not propagate itself. Trojans are tricky, in that
considered to be "malware", also commonly referredthey are often disguised as some type of useful or
to as malicious software. Spyware and adware alsointeresting software. When the software is installed
fall into the category of malware, as is any other type(Trojans are normally embedded in .exe files), the
of software that is designed to perform malicious andTrojan is activated, and sometimes you don't even
or unwanted activity.realize its there.
Viruses, worms, and Trojans have been around forTrojans can do many things, and while some are
awhile, and are often packaged together (i.e. a virusdesigned to be dangerous, others are just annoying. A
that launches a worm when executed, a worm thatTrojan might destroy files, change your desktop icons,
plants a Trojan, etc...). Because of their longstandingor plant a "backdoor" on your system that can be
use as a means of performing disruptive andused by a hacker or cyber criminal at a later date.
destructive tasks, anti virus software developersTrojans are usually passed from PC to PC by email or
include protection against Trojans and worms in theirdisk file transfer, because the sender doesn't know
antivirus applications.that the file carries a harmful Trojan.
Anti virus software (if updated regularly) will helpProtection from Viruses, Worms, and Trojans
protect you from all three dangers.The good news is that Antivirus software will provide
Differences Between Computer Viruses, Worms, anda great deal of protection against known computer
Trojan Horsesviruses as well as worms and Trojan horses. The bad
A Computer Virus is attached to a program or file, andnews is that antivirus software won't necessarily
is designed to spread from one computer to another. Itprovide total protection. You still need a good firewall
infects the computer it is installed on, and is usuallyto keep cyber criminals out, and you need anti
spreads when the infected file (usually an .exe file) isspyware to protect against the other types of
shared with others via email, disk, USB drive, or CD. Amalware that antivirus software isn't so good at
virus has to have human action in order to launch andcatching. For the absolute best protection, use a
deliver its "payload".Computer Security Suite.
The file that the virus is attached to cannot open itself;Be sure to get the most recent updates for your
a user has to open it in order to execute the virus.operating system and all applications installed on your
Viruses have many symptoms, depending on thePC. This is especially important for Windows users, as
intent. Computer viruses can erase or corrupt files andthe majority of malware is designed to work on the
applications, crash your system by making so manyworld's most popular operating system. Updates will
copies of files that the hard drive fills up, or make apatch newly discovered "security holes" and will help
computer inoperable by altering critical system files.prevent many viruses, worms and Trojans from
A Computer Worm is like a virus in that it is alsocompleting their "mission".