Computer viruses have been a source of trouble for individuals and businesses for decades. Their malicious strength ranges from mildly annoying to incredibly destructive. In some cases, they can wipe out entire computer systems, or even whole networks if durable enough. To know how to properly combat these vicious foes, you must understand how a virus functions and some of its basic properties and characteristics.

Viruses are computer programs, designed by an individual or team to infect a device without the user becoming aware of the breach. The main purpose of a virus is to corrupt the files of a computer and ultimately render the system useless. Many viruses are launched by hackers simply for their own personal entertainment in fact, some of the most malicious viruses in history have this root. Sometimes, the goal is more productive, such as wanting to destroy a competitor’s computer network to make one’s own business stronger.

People often get confused as to the differences between viruses, worms, adware, malware, and Trojan horses. The defining characteristic of a virus is that it needs to attach itself to a program, or host, in order to replicate and spread. Worms, on the other hand, can survive on their own without a host. Adware does not exactly have a malicious intent, although few computer users want it on their systems, as the software displays advertising even when the user is not on any web pages.

Trojan horses appear to be harmless files, but actually open the door to hackers to further devastate or commandeer a node. Malware is an umbrella term which covers everything previously mentioned, plus unique software which does not fit the characteristics of other programs but is still malicious.

The best way to avoid viruses is to not receive them in the first place. You can steer clear of the majority of viruses by simply being careful. Being careful includes not opening spam emails, not downloading programs you are not familiar with, and putting strong passwords on to all of your computer accounts. If you take a strong amount of caution in all of your computing activities, there is a good chance you will not ever have to deal with a virus-related problem.

However, sometimes infections are unavoidable. Viruses travel from file to file, corrupting each one, and they travel from computer to computer when one of those corrupted files is sent out. A friend or coworker could unknowingly send out a corrupted file, thus infecting every recipient.

Businesses have become aware of the consumer and industrial need for virus protection. Several companies, such as McAfee and Avast, sell anti-virus software which automatically scans for viruses, worms, and every other type of malware. Whenever the program finds something particularly strong, it notifies the user and offers them several options, such as deleting or quarantining the threat. Garden variety viruses are rooted out in daily scans, and although these kinds of viruses may not be serious, they do inhibit the operational speed of any computer.

Anti-virus programs must be updated on a regular basis, so the software’s registry can be filled with new virus signatures, which are unique strings of bits inherent to different viruses. Certain viruses are labeled as metamorphic, in that they change each time they are copied, making them hard to track. As long as your anti-virus software is kept up to date, you should be able to contend with anything that is thrown at you.

Could the mass media hype about computer viruses actually make the problem worse?

If you believe what you hear in the media, there are an awful lot of viruses going around. No, I′m not talking about the make-you-sick kind of virus, though they get plenty of airtime, too. I′m talking about the kind of virus that enters via your internet connection rather than your nasal passages.

What the mainstream media often don′t tell you–at least, in most radio and television newscasts and in the crucial headlines and opening paragraphs of newspaper articles– is that many of these “viruses” are not viruses at all.

What Computer Viruses Really Are

The main reason the mainstream media always are in alarm over viruses is that they tend to call any malicious computer program a virus. In reality, there are at least eleven distinct types of malicious software, or malware, commonly affecting computers today. The most common of these are worms, Trojans, and spyware.

So, what’s the difference between computer viruses and the other types of malware? The difference is that computer viruses are just about the only ones that regularly shut down computers and cause other obvious damage. The most common of the other kinds of malware–worms, Trojans, and spyware–are usually only detectable with a special scan.

The Real Danger of Computer Viruses

If the other types of malware are so unobtrusive that they can only be detected with a special scan, then what’s to worry about? For starters, these programs are called malicious for a reason: they are designed to cause some kind of damage, if not to your computer, then to someone else’s.

Worms are most famously used to damage, destroy, or disrupt other computer networks than the one on which the host computer is located. For instance, worms have been used by website owners to shut down rival websites by sending overwhelming numbers of requests to the computer that hosts that website. Worms have also been used to send out viruses to other computers, often without infecting the host machine–after all, what would it benefit the worm to shut down its host computer?

Trojans, in turn, are often used to insert worms and other malware on your computer, even if the Trojan itself does no damage.

But even if you don′t care what happens to anyone else, you should still be concerned about one kind of malware: spyware, a kind of malware that, true to its name, collects data from your computer and sends it back to a remote host.

Most spyware is only interested in monitoring your internet usage so it can tell other programs, called adware, what advertising to popup on your computer. However, there are criminal spyware programs that steal financial data, or perform a thorough identity theft. Don′t think you have personal or financial data on your computer? Some spyware programs contain a key logger, which is a program that copies whatever you type, usually in order to snatch passwords. Even if you keep no financial information on your computer, if you ever buy anything over the web, the key logger would allow its owner to buy stuff using the same information you typed in to buy stuff yourself.

Why Blame the Media?

Given the danger of all these different types of malware, isn′t it a good thing that the mass media are becoming hysterical about it? And can′t they be forgiven the sloppy reporting of calling Trojans, worms, spyware, and other malware “viruses”?

No, no, no.

This is a classic case of bad reporting doing more damage than no reporting at all. In this case, the damage bad reporting has done is to promote a common myth that goes something like this: “The only malicious software is a virus. Viruses damage your computer. Therefore, if my computer is working OK, my computer has no malicious software. I only need to scan my computer for problems when there is a sign of problems.”

Thanks to this myth, many people complacently let their antivirus software go months out of date, not wanting to be bothered with scheduling an automatic update. Just as bad, many people don′t have any extra software to combat the other types of malware that may not be covered by antivirus software.

In fact, it’s not uncommon for people who have found malware on their computers after a scan to say, “But I never had malware on my computer before!” But how would they have known if they had never scanned!

Until the biggest mainstream media–and especially television–start educating the public about the need to have their computers automatically scanned at least daily, the world will continue to have major, drawn-out problems with malware that could have been wiped out as soon as soon as the anti-malware software makers discovered it.

And until that day, the mainstream media will have many more opportunities to run hysterical stories about “viruses,” thereby forcing them to sell more newspapers and broadcast to even larger audiences of people who suck at the information trough yet somehow never become full.

Today I want to talk a little about the dreaded computer virus. The goal of this article is to teach you, the home user, the fundamental skills needed to help detect, remove, and most importantly prevent viruses from infecting your computer. As the owner of a computer consulting business, I have seen 1st hand how much damage computer viruses can do. To help protect yourself from a virus attack, it will be necessary to understand exactly what a virus is. A virus is essentially a software program designed with malicious intentions, to copy itself and spread from one computer to another. What makes a virus so dangerous is what they are designed to do.

A virus, once installed on your computer, can easily corrupt or delete data from your computer. This can be anything from your latest Word document to the irreplaceable pictures of your loved ones. We will get into exactly what a virus can do later in this article. Now that you have an idea of what a virus is and what it can do to your computer, lets discuss how your computer gets infected. I have heard countless times from people, ” But I did not open any email attachments, how can I be infected?” While it is true that a majority of viruses are hidden within email attachments, they can also be downloaded into our computers in the form of images, videos, or even instant messages. I have personally removed a virus from Cd’s, jump drives, and floppy disks.

Lets talk about ways to help protect your computer from viruses. To protect your computer from these threats it is vital that you have an anti virus program installed and up to date. I have seen many times in the field computers that have anti virus programs but still are infected with a virus. Let me point out that not all anti virus programs are equal. I will not discuss in this article which anti virus program you should or should not use however email me and I will be happy to help you in that aspect. Your anti virus program will do you little good if you do not keep your definitions up to date. New virus are being identified all the time so it is vital to keep your anti virus program up to date on the latest threats. Another proven method is to use a firewall.

A firewall is essentially software or hardware that is designed to filter out information that is being sent to or from your computer. Think of a firewall as a Guard at the end of your driveway, before anyone enters your home they must first pass a set of rules or security checks you have given before they are allowed to enter your home. Some of the software-based firewalls include Norton Internet Security, Zone Alarm and Trend Micro. You may be using a hardware firewall and not even know it. If you have a LAN (Local area network) then chances are you have a router of some kind. Most routers come built in with a firewall, which is very effective at protecting your computer from viruses. Another technique used to help prevent viruses is to keep your computer up to date. If you are using a windows based PC, check Windows Update often for any security patches that are released.

Do not open email attachments if you do not know the sender, this is asking for trouble. Lets move on to identifying infected computers. As a PC technician, it is my responsibility to quickly identify the signs of virus infections. Computers with virus infections will often show some of the following symptoms. Please note, that the issues listed below may be caused by several problems, such as spyware, and are not specific to viruses. Your computer may be slow to start or shut down. You may be missing data on your hard drive or, in worst case scenarios, lose all data on the drive. You may experience strange error messages or you computer will shut down unexpectedly. Your fonts may be distorted and overlap or you may experience difficulties in printing.

These are just some examples of the harm viruses can do. Now the most difficult part, removal. This is a topic worthy of its own article as there are many different procedures in virus removal. I will discuss with you the very basics. If you think you are the victim of a virus do a thorough scan of your computer. It may also be beneficial if you scan your hard drive while in safe mode. This is usually accomplished by tapping F8 at start up, but refer to your computer’s manual for instructions to be certain.

If you do not have an anti virus program, first thing to do is get one! In the meantime you may use the services of an online virus removal tool. Many of the popular anti virus programs offer this service. My intent of this article was to help inform you of the dangers virus threats can pose, as well as giving you the knowledge to help detect, remove and prevent these threats. I hope I have accomplished this, and you can walk away after reading this article, feeling more confident of your abilities to protect your computer from virus threats.

Every day new computer viruses are created to annoy us and to wreak havoc on our computer systems. Below are ten viruses currently cited as being the most prevalent in terms of being seen the most or in their ability to potentially cause damage. New viruses are created daily. This is by no means an all inclusive list. The best thing you can do is to remain vigilant, keep your anti-virus software updated, and stay aware of the current computer virus threats.

Virus: Trojan.Lodear
A Trojan horse that attempts to download remote files. It will inject a .dll file into the EXPLORER.EXE process causing system instability.

Virus: W32.Beagle.CO@mm
A mass-mailing worm that lowers security settings. It can delete security-related registry sub keys and may block access to security-related websites.

Virus: Backdoor.Zagaban
A Trojan horse that allows the compromised computer to be used as a covert proxy and which may degrade network performance.

Virus:W32/Netsky-P
A mass-mailing worm which spreads by emailing itself to addresses produced from files on the local drives.

Virus: W32/Mytob-GH
A mass-mailing worm and IRC backdoor Trojan for the Windows platform. Messages sent by this worm will have the subject chosen randomly from a list including titles such as: Notice of account limitation, Email Account Suspension, Security measures, Members Support, Important Notification.

Virus: W32/Mytob-EX
A mass-mailing worm and IRC backdoor Trojan similar in nature to W32-Mytob-GH. W32/Mytob-EX runs continuously in the background, providing a backdoor server which allows a remote intruder to gain access and control over the computer via IRC channels. This virus spreads by sending itself to email attachments harvested from your email addresses.

Virus: W32/Mytob-AS, Mytob-BE, Mytob-C, and Mytob-ER
This family of worm variations possesses similar characteristics in terms of what they can do. They are mass-mailing worms with backdoor functionality that can be controlled through the Internet Relay Chat (IRC) network. Additionally, they can spread through email and through various operating system vulnerabilities such as the LSASS (M⁰-011).

Virus: Zafi-D
A mass mailing worm and a peer-to-peer worm which copies itself to the Windows system folder with the filename Norton Update.exe. It can then create a number of files in the Windows system folder with filenames consisting of 8 random characters and a DLL extension. ∜/Zafi-D copies itself to folders with names containing share, upload, or music as ICQ 2005a new!.exe or winamp 5.7 new!.exe. ∜/Zafi-D will also display a fake error message box with the caption “CRC: 04F6Bh” and the text “Error in packed file!”.

Virus: ∜/Netsky-D
A mass-mailing worm with IRC backdoor functionality which can also infect computers vulnerable to the LSASS (MS04-011) exploit.

Virus:∜/Zafi-B
A peer-to-peer (P2P) and email worm that will copy itself to the Windows system folder as a randomly named EXE file. This worm will test for the presence of an internet connection by attempting to connect to www.google.com or www.microsoft.com. A bilingual, worm with an attached Hungarian political text message box which translates to “We demand that the government accommodates the homeless, tightens up the penal code and VOTES FOR THE DEATH PENALTY to cut down the increasing crime. Jun. 2004, Pécs (SNAF Team)”

Anne Wolski has worked in the health and welfare industry for more than 30 years. She is the owner of http://www.mummansun.com, a discount retail outlet, and a co-director of http://www.betterhealthshoppe.com which is an information portal with many interesting medical articles. She is also an associate of http://www.timzbiz.com which features many articles on internet marketing and resources.

Whether you have learned your lesson from a past experience with a nasty computer virus or have been pressing your luck by surfing the web and downloading various files or opening those email messages sent to you by people you don’t know without any real understanding of just how vulnerable you really are each time you log onto your computer.

You now have the opportunity to discover what steps you can take to avoid such an annoying and many times destructive infestation.

Listed below are some of the guidelines you can follow in order to keep those nasty viruses from making a mess out of your computer and your life.

*Purchase and install a well respected antivirus software program and be sure to set it up so that it automatically runs when the computer starts up each time.

*Make sure to keep your antivirus software up to date by either using the automatic update feature that many come with or make it a habit to manually check at least once or twice a week for updates on your own.

*Set your antivirus program to scan for potential viruses each time you open a word-processing document like the ones that get sent through email. Viruses found in word-processing documents are called Macro Viruses.

*When purchasing software make sure to only buy from vendors that are well known and from ones you trust.

*Resist swapping data with the use of floppy disks or other mobile storage devices between various computers. If exchanging programs between computers is unavoidable just make sure to scan the storage device(s) for viruses before transferring data from one computer to the next.

*If using floppy disks to transfer data make sure to format them before using them for the first time.

*Never use pirated software. This is both illegal and a very good way to invite an unwanted computer virus.

*When downloading software from the internet do so as little as possible. There are many neat programs available on the internet, but unfortunately there are many viruses that go along with them also.

*If you must download programs from the internet ALWAYS scan them for viruses BEFORE opening them up to install on your computer.

*Probably the most important and neglected method of disaster recovery are periodic backups of all important files found on your computer. Should a virus happen to get through your lines of defense you may need to replace the virus corrupted files with fresh ones that have been kept for such an occasion.

Finally, it is not guaranteed that if you follow the above steps that you will not be the victim of a computer virus, but you can sure bet that if followed you will greatly reduce the chance of being an unsuspecting recipient of such an unwanted program.

As more and more people are becoming comfortable using their computers at school, home or in the office it’s only a matter of time before they encounter a computer virus. Here are our top 10 steps to protect you from computer viruses.

Use a high quality anti-virus program. There are many different anti-virus computers programs on the market some of them are better than others. Look to reputable computer magazines or websites for ratings to help you find the one that matches your needs.

Always use your anti-virus software. Make sure your anti-virus software is always turned on and scanning, incoming and outgoing email messages, and any software programs you run.

Keep your antivirus programs up to date. Most programs come with a yearly subscription make sure you take advantage of the updates. More advanced programs allow you to schedule updates or full system scans for “off hours” like 2AM when you aren’t likely to be using your computer.

Keep your computer up to date. From time to time operating systems fall victim to security holes or issue updates. Make sure you check periodically to make sure you are running stable up to date versions of your software.

Backup your data regularly. Most windows computer users keep their documents in the “My documents” folder. This makes it easy to back up all of your important documents. Make weekly or monthly copies to CD or USB drives.

If you use floppy disks or USB drives on public computers like your school computer lab, Kinko’s, or even digital photo printing store make sure you scan them for viruses. Public computers are notorious for not being up to date and properly protected.

Be wary of email attachments. Treat any email attachment as potentially dangerous. Never open attachments from people you weren’t expecting. Also be careful of attachments from people you know but weren’t expecting. Many computer viruses replicate themselves by reading the contacts from an infected computer.

Use text email if possible. While HTML email is prettier and allows you more control over formatting it also can carry computer viruses. If you use text based email the only way to get a virus is by opening an attachment.

Use downloaded freeware and shareware files or software with caution. Try to download them from popular reputable sources that scan the programs before they are uploaded. To make sure you are safe scan the program before you install it on your computer.

Be wary of links in IM or instant messaging software. Don’t accept invitations from people you don’t know and never click a link from someone you don’t trust, they can easily redirect you to another website that will try to install a virus on your computer system.

In information security , computer virus is a manmade program or piece of code that is loaded onto your computer without your knowledge and runs against your wishes. From behavior computer virus in a way is a similar biological virus which pervasions by inserting itself into living cells. Cell by cell and all organisms (computer) is ridden virus cells.

Without computer viruses there are separated two other types of malicious computer programs - viruses.

Trojan Horses

As already from this virus type name we can imagine, Trojan horses are programs that pretend to be legitimate software, but actually carry out hidden, harmful functions. Trojans can’t replicate themselves that mean, they can’t expand so fast as other virus types. But often they work together with viruses.

Worms

Worms are similar to viruses but do not need a carrier program or document. Worms simply create exact copies of themselves and use communications between computers, for example e-mail, to spread.There are different types of computer viruses with different influence. Some viruses are fairly harmless or only annoying, but there are viruses that can create inconceivable damages.

Some things what virus can do with computer:

* Slow down e-mail – generating huge e-mail traffic and slowing down servers

* Steal confidential data – for example, recording user’s keystrokes

* Use your computer to attack websites

* Let other user hijack your computer – allowing to connect to your computer and use it for their own purpose;

* Corrupt data – making changes in some documents

* Delete data – all or only some part data on your HDD

* Play pranks

* Damage credibility – forwarding itself from your computer to your friends or even business partners

* Cause embarrassment - for example, replacing one word in all documents with other.

Every year computer viruses activity brings to company several million dollars damages. Year for year this number of damage increase!

Because it is so important that every people get information security awareness training!

Computer virus can really be a real treat to our very existence. Since the onset of computers, they already have become an integral part of our daily lives. Especially with the onslaught of the Internet, we now depend on computers so much from our files, to address book, to information sources, to connecting with friends, etc.

A properly designed and executed virus can have a very disabling effect on our computer. Computer viruses then show us how vulnerable we can be and how human beings became so intricate with computers and technology in so many aspects in their lives.

A computer virus is like any program. However, the goal of every computer virus is to destroy files or computer systems by spreading itself in such a fast phase to unsuspecting computer users.

In order to protect your computers from these damaging and disabling viruses, we must be vigilant and employ all possible defenses against them. So let antivirus program be your first line of defense against the paralyzing effects of computer viruses.

Best tip yet, be sure to install anti-virus program from a reputable source. It is rather important to update and use the anti-virus program regularly. Everyday, new viruses come out so if you have an outdated antivirus program, it will not provide you with the much-needed protection your computer may require.

Take note that there are several reliable antivirus programs that can be downloaded for free, these are called antivirus freeware. Antivirus downloads can secure your computer and your very life. Make it a habit to check antivirus online help for updates on viruses to guard your computer before the virus hits you off-guard, which can surely bring out in you an unrelenting ogre.

The most common sources of viruses are from online chat sessions so be extremely careful about accepting programs and files. Computer virus creators are also Internet mainstays. They are these technologically gifted individuals who just want to create havoc out of their expertise, and that is creating computer viruses. So they frequent online chat rooms with the intention of generating tons of unsuspecting victims. And then, spreading the venom they just created would never be a problem because of the myriad of online chat users logging on and off.

Be sure to make backup copies of your most important files, ideally in separate CDs, DVDs, and USB drives. So if ever a virus infected your computer, you will not be at a loss.

If a virus already entered your computer, follow the directions in your antivirus freeware or antivirus downloads on how to clean it. And if you need assistance, do not hesitate to check the antivirus online support services of your antivirus freeware.

But don′t get intimated by computer viruses, as long as you have back up for your files, viruses can never annoy you anymore. In fact, today, viruses are somewhat not that disabling as before due to the popularity of reputable antivirus freeware, antivirus downloads, and antivirus online helps. So if you got the viruses from the Internet, you can likewise get rid of them also through the Internet.

A computer virus is something that can literally cripple your computer, depending on the severity. They come in different levels of severity from mild to dangerous and everywhere in between.
What is a computer virus?

So, what is a computer virus, not only is it something that can damage the performance and life of your computer, but your mental well being as well. Combating a virus, without the help of anti-virus software such as AVG internet security, can be extremely nerve wracking and depressing because it can literally affect various parts of your computer.

How are computer viruses distributed?

Computer viruses are distributed in many different ways. One of the most common methods of distribution is via email. Some of the most widespread and destructive viruses are distributed via email. Typically, they come in an email that looks completely legitimate and they can even come disguised with an email you might be familiar with. Some viruses are simply spread by opening the email or by downloading an attachment. Many free emails such as Yahoo come with email virus scanners installed, which will not allow you to download the attachment if it detects a virus.

Another method of virus distribution is via internet downloads. These viruses are bundled in a download and typically come from websites with hacks or peer to peer programs.

When asking the question, what is a computer virus, you should also ask how you can combat or prevent the viruses from affecting your computer. There are many programs available to help you detect, remove, and prevent viruses. One of the most popular and best programs to date is AVG Internet Security, or any of the AVG products.

AVG, a product created by Grisoft, is an excellent software program that is perfect for detecting and removing computer viruses. Their internet security program not only provides anti-virus protection for your computer from Trojans, worms and viruses, but it also includes anti-spyware and anti-spam protection against phishing, spam, malware, adware and spyware. Additionally, AVG internet security provides protection with a firewall, preventing hackers from accessing your computer.

AVG is the best and easiest to use all in one program available for computer protection. You are constantly made aware of instant definition updates and program versions, as well as twenty-four hour a day technical support.

So if you want to find out just what is a computer virus and how computer viruses are distributed, AVG is a great place to start. Not only can you get the best protection, but a number of resources are available to you as well. This enables you to learn about the latest virus threats and how you can eliminate the possibility of infection on your computer.

Nowadays, the term of Computer Virus sound familiar for us. Every day we heard millions computer infected by a Computer virus, or a virus make Internet connection trouble, and many more. A computer virus is a computer program that can copy itself and infect a computer without authorization or knowledge of the computer user. Virus can destroy your data, damaging programs, steal important information, or reformatting the hard disk to make your computer completely useless.

If you ask how virus infects a computer, there’s a many way to make it possible. A Floppy Disk, a CD, USB Flash Disk, Zip Drive or even Internet. Today, a virus able to infect a computer from Internet, or network services such World Wide Web, e-mail, Instant Messaging and file sharing systems. Some virus even no needs human action to spread itself. They able to use Operating System bug to infect a computer.

So, now you know what is a computer virus and want to prevent your computer from virus. Or maybe, your computer already infected by virus. Don’t worry. I will help you for solve this problem.

First, install an anti virus program. If a computer virus is programmed to damage the computer, then an anti virus is programmed to prevent, destroy and heal your computer from virus. There’s a many anti virus today. You can use Norton Antivirus, Kaspersky Antivirus, Panda Antivirus or AVG Antivirus. If you don’t have an anti virus, then get one for you. Buy it from computer software store or download from Internet. And make sure to buy or download the latest release. And the most important things are make your anti virus definition up-to-date. Most of anti virus have an automatic update system. You only need to connect your computer to Internet and let them do it automatically. An up-to-date anti virus makes the anti virus know the latest virus and how to remove them.

If you connected to Internet, you need to install a firewall program. A firewall is a computer program designed and programmed to watch an Internet connection on your computer. And if there is an unusual action, they prevent the action. Or in other word, a firewall is a “police” to watch Internet and prevent “bad thing” do some action on your computer. You can use software-based firewall like Norton Internet Security, Zone Alarm and Trend Micro.

Always update your Operating System. There is no perfect Operating System, nor Windows, Linux or Macintosh. There are many bug on them. Usually, an Operating System vendor release a bug fix to patch the bug. So, you need to update your Operating System. Up-to-date Operating System also make your computer immune from another threats.