Q: What is a computer virus?
A: A computer virus is a program, piece of code, or programming script which runs without the user's knowledge and performs destructive or otherwise unwanted actions to a computer such as disabling or over-riding security features and making it vulnerable to other attacks. Computer viruses range from annoying and harmless, to extremely dangerous and destructive. Viruses normally replicate themselves by propagating throughout files. Viruses are normally spread by email, through a computer network, via floppy disks, or via the Internet.
Q: How do I know if my computer is infected with a virus?
A: The only way to be certain if your system is infected is to run a virus scan using antivirus software. Some indicators that your computer may have been infected with a virus include:
? runs consistently slower than usual
? frequently stops responding
? crashes and restarts
? applications no longer work properly
? inaccessible disks or disk drives
? you see distorted windows and dialog boxes
? files being deleted for no known reason
? strange error messages
? strange behavior with your email program
Q: How do computer viruses spread?
A: The most common way for computer viruses to spread to other computers is through email. Other methods include file sharing programs, from a website - execution of malicious javascript or vbscript, transferring files from an infected computer to another computer (with a floppy disk, CD-ROM, etc.). Some viruses can even spread through a network connection.
Types Of Viruses
Not all computer viruses behave, replicate, or infect the same way. There are several different categories of viruses and malware. Below I list and discuss some of the most common types of computer viruses.
Trojan Horse:
A trojan horse program has the appearance of having a useful and desired function. While it may advertise its activity after launching, this information is not apparent to the user beforehand. Secretly the program performs other, undesired functions. A Trojan Horse neither replicates nor copies itself, but causes damage or compromises the security of the computer. A Trojan Horse must be sent by someone or carried by another program and may arrive in the form of a joke program or software of some sort. The malicious functionality of a Trojan Horse may be anything undesirable for a computer user, including data destruction or compromising a system by providing a means for another computer to gain access, thus bypassing normal access controls.
Worms:
A worm is a program that makes and facilitates the distribution of copies of itself; for example, from one disk drive to another, or by copying itself using email or another transport mechanism. The worm may do damage and compromise the security of the computer. It may arrive via exploitation of a system vulnerability or by clicking on an infected e-mail.
Bootsector Virus:
A virus which attaches itself to the first part of the hard disk that is read by the computer upon bootup. These are normally spread by floppy disks.
Macro Virus:
Macro viruses are viruses that use another application's macro programming language to distribute themselves. They infect documents such as MS Word or MS Excel and are typically spread to other similar documents.
Memory Resident Viruses:
Memory Resident Viruses reside in a computers volitale memory (RAM). They are initiated from a virus which runs on the computer and they stay in memory after it's initiating program closes.
Rootkit Virus:
A rootkit virus is an undetectable virus which attempts to allow someone to gain control of a computer system. The term rootkit comes from the linux administrator root user. These viruses are usually installed by trojans and are normally disguised as operating system files.
Polymorphic Viruses:
A polymorphic virus not only replicates itself by creating multiple files of itself, but it also changes it's digital signature every time it replicates. This makes it difficult for less sophisticated antivirus software to detect.
Logic Bombs/Time Bombs:
These are viruses which are programmed to initiate at a specific date or when a specific event occurs. Some examples are a virus which deletes your photos on Halloween, or a virus which deletes a database table if a certain employee gets fired.
Ways to Prevent Computer Viruses
It doesn?t matter if you?ve been on the Internet for five minutes or five years, you?ve probably thought about ways in which you can prevent a computer virus from entering your machine. A virus can compromise your personal information and even destroy your computer completely. Luckily, there are many low cost things you can do to protect yourself and stay one step ahead of the hackers. Here are 11 things you can do to help prevent computer viruses from invading your computer.
1. Install a reliable anti virus program ? From the first moment you turn your computer on, you should have a trusted anti virus program by your side. Even if you have a machine that isn?t hooked up to the Internet, a reliable anti virus program is a low cost and common sense addition to any machine. There are even free anti virus programs you can download that work almost as well as industry giants like Norton, Kaspersky, Bitdefender and McAfee.
2. Install anti-spyware and anti-malware programs ? As good as the best anti virus programs are, they sometimes need a little bit of help. Thankfully, many of the top anti-spyware programs are completely free. Spybot Search and Destroy and CCleaner are just two free programs that can help prevent computer viruses from doing any damage on your machine. As helpful as these programs are, however, you must update them and run them on a regular basis for them to do any good.
3. Avoid suspicious websites ? A good virus protection program will alert you when you visit a website that attempts to install or run a program on your computer. Many less than reputable adult websites do this, so if you get a warning, don?t go back, you may end up with a bug you can?t get rid of.
4. Never Open Email Attachments Without Scanning Them First ? The most common way viruses are spread throughout the Internet is still via email. Some attachments, like pictures, now display in emails and don?t require an attachment to be manually opened, but other documents do. Make sure you use an email client that scans all email attachments before you are allowed to open them. This will help prevent computer viruses from getting a foothold on your machine.
5. Set up Automatic Scans ? Many of the top anti virus programs, as well as the best anti-spyware programs, now have settings that will let them automatically run during down times or in the middle of the night. Of course, your computer must be on for this to happen, but having daily scans run when nothing else is going on is a great way to prevent even the latest computer viruses from sticking around too long.
6. Watch Your Downloads ? Part of the fun of the Internet is downloading music, movies and other items. However, since these downloads are so massive, it can be easy to sneak a virus along for the ride. Only download these files from trusted sites that you can count on, or, at the very least, scan them before you open them.
7. Updates, Updates, Updates ? There is a reason why Windows has a feature called Critical Updates. There is an entire branch of Microsoft dedicated to staying one step ahead of the hackers out there so when they manage to fix a possible security loophole, you need to download the patch right away. Help Microsoft help you prevent computer viruses from causing too much trouble.
8. Know What To Look For ? Even if you are just a casual computer user, you should have an idea of how your machine operates, what normal pop up windows look like and what popular viruses are out there, that way, when your computer begins exhibiting tell tale signs, you?ll know. You can help prevent computer viruses by staying updated and educated.
9. Stay Away From Cracked Software ? It is so secret that you can download illegal, cracked versions of some programs online. As tempting as it may be, these files are almost always infested with advanced and difficult to detect bugs. Play it safe and get your software from the source.
10. Install a Firewall ? A firewall is a program that screens incoming Internet and network traffic. Along with your virus program, it can help prevent unauthorized access to your computer.
11. Be prepared to Lock Down ? If you hear of a virus that is spreading like wildfire through the Internet, make an extra effort to be careful. Don?t open any suspicious emails or accept any downloads for a week or two until your virus protection program has been updated and you are, once again, safe.
Top 10 Antivirus Softwares
Antivirus software is must-have protection. This review picks the best antivirus software based on its virus detection abilities, features, and breadth of protection. Whether you're seeking total system coverage or an ala carte solution, each of the following products provides superb virus protection for Windows-based PCs. Because every system is unique, evaluate several of Windows XP and Windows Vista antivirus scanners to find the software best suited for your PC and your level of experience.
1. Norton Internet Security 2009
Symantec's antivirus products have historically always provided excellent detection and removal of malware. On the downside, that protection came at the price of often crippling system performance. That's now a thing of the past. Performance overhauls are the hallmark of Norton Internet Security 2009, which features 'pulse updates' to deliver more frequent and thus smaller signature updates, whitelisting to streamline scan times, and a lighter, sleeker footprint that installs in mere minutes.
2. Avira AntiVir PersonalEdition Premium
AntiVir is a consistent leader in independent antivirus tests. Avira's AntiVir PersonalEdition Premium is a low-impact, easy to use virus scanner that also the ability to make an antivirus rescue CD for your system. Also includes WebGuard to protect against malicious or compromised websites. Five euros of each purchase is automatically donated to the Auerbach Foundation, a non-profit that supports various charity and community-related services. AntiVir PersonalEdition Premium should be used in conjunction with a firewall.
3. McAfee VirusScan Plus
McAfee VirusScan Plus is an ideal candidate for those seeking an antivirus/firewall combination without all the bloat of traditional Internet security suites. McAfee VirusScan Plus makes an easy job of removing adware and spyware, something not all antivirus products deliver. SiteAdvisor service is including, helping to guard against malicious websites.
4. Kaspersky Anti-Virus Personal
Kaspersky Anti-Virus Personal offers excellent antivirus protection, perhaps unsurpassed in its ability to unpack and scan compressed files - something that trips up a lot of other vendors. Should be used in conjunction with a firewall.
5. Panda Antivirus Pro 2009
Panda Antivirus Pro 2009 combines antivirus, antispyware, antiphishing and a firewall with its highly touted behavior-based TruPrevent Technology. License covers use on up to three computers and includes free tech support via email (telephone support options are also available).
6. BitDefender Antivirus Plus
Softwin's BitDefender Professional protects against viruses, spyware, and instant messaging threats, as well as offering firewall rules to block undesirable traffic and a privacy gateway to keep your identity and preferences private while surfing the Internet.
7. Eset Nod32
Nod32 features a small footprint, low performance hit, and fast scan speeds, providing focused virus protection ideal for gamers or those with an older PC. Should be used in conjunction with a firewall.
8. AVG Anti-Malware
AVG Anti-Malware combines traditional virus protection with adware and spyware scanning, in a low impact footprint ideal for resource-strained PCs or those who just want the best performance possible out of their computers. Free tech support is available via email and the standard license includes two years of protection. Should be used in conjunction with a firewall.
9. G Data AntiVirusKit (AVK)
AntiVirusKit (AVK) provides a double layer of protection, bundling two of the best antivirus engines - Kaspersky and BitDefender - under a single, easy-to-use console. You'll want to bolster G Data's AVK with a firewall.
10. F-PROT Antivirus
F-PROT Antivirus for Windows offers a feature that's increasingly harder to find - it includes a command-line scanner that can be used to create a rescue CD for scanning the system in Safe Mode. This is a particularly effective way to remove stubborn resuscitators. Firewall not included.
A: A computer virus is a program, piece of code, or programming script which runs without the user's knowledge and performs destructive or otherwise unwanted actions to a computer such as disabling or over-riding security features and making it vulnerable to other attacks. Computer viruses range from annoying and harmless, to extremely dangerous and destructive. Viruses normally replicate themselves by propagating throughout files. Viruses are normally spread by email, through a computer network, via floppy disks, or via the Internet.
Q: How do I know if my computer is infected with a virus?
A: The only way to be certain if your system is infected is to run a virus scan using antivirus software. Some indicators that your computer may have been infected with a virus include:
? runs consistently slower than usual
? frequently stops responding
? crashes and restarts
? applications no longer work properly
? inaccessible disks or disk drives
? you see distorted windows and dialog boxes
? files being deleted for no known reason
? strange error messages
? strange behavior with your email program
Q: How do computer viruses spread?
A: The most common way for computer viruses to spread to other computers is through email. Other methods include file sharing programs, from a website - execution of malicious javascript or vbscript, transferring files from an infected computer to another computer (with a floppy disk, CD-ROM, etc.). Some viruses can even spread through a network connection.
Types Of Viruses
Not all computer viruses behave, replicate, or infect the same way. There are several different categories of viruses and malware. Below I list and discuss some of the most common types of computer viruses.
Trojan Horse:
A trojan horse program has the appearance of having a useful and desired function. While it may advertise its activity after launching, this information is not apparent to the user beforehand. Secretly the program performs other, undesired functions. A Trojan Horse neither replicates nor copies itself, but causes damage or compromises the security of the computer. A Trojan Horse must be sent by someone or carried by another program and may arrive in the form of a joke program or software of some sort. The malicious functionality of a Trojan Horse may be anything undesirable for a computer user, including data destruction or compromising a system by providing a means for another computer to gain access, thus bypassing normal access controls.
Worms:
A worm is a program that makes and facilitates the distribution of copies of itself; for example, from one disk drive to another, or by copying itself using email or another transport mechanism. The worm may do damage and compromise the security of the computer. It may arrive via exploitation of a system vulnerability or by clicking on an infected e-mail.
Bootsector Virus:
A virus which attaches itself to the first part of the hard disk that is read by the computer upon bootup. These are normally spread by floppy disks.
Macro Virus:
Macro viruses are viruses that use another application's macro programming language to distribute themselves. They infect documents such as MS Word or MS Excel and are typically spread to other similar documents.
Memory Resident Viruses:
Memory Resident Viruses reside in a computers volitale memory (RAM). They are initiated from a virus which runs on the computer and they stay in memory after it's initiating program closes.
Rootkit Virus:
A rootkit virus is an undetectable virus which attempts to allow someone to gain control of a computer system. The term rootkit comes from the linux administrator root user. These viruses are usually installed by trojans and are normally disguised as operating system files.
Polymorphic Viruses:
A polymorphic virus not only replicates itself by creating multiple files of itself, but it also changes it's digital signature every time it replicates. This makes it difficult for less sophisticated antivirus software to detect.
Logic Bombs/Time Bombs:
These are viruses which are programmed to initiate at a specific date or when a specific event occurs. Some examples are a virus which deletes your photos on Halloween, or a virus which deletes a database table if a certain employee gets fired.
Ways to Prevent Computer Viruses
It doesn?t matter if you?ve been on the Internet for five minutes or five years, you?ve probably thought about ways in which you can prevent a computer virus from entering your machine. A virus can compromise your personal information and even destroy your computer completely. Luckily, there are many low cost things you can do to protect yourself and stay one step ahead of the hackers. Here are 11 things you can do to help prevent computer viruses from invading your computer.
1. Install a reliable anti virus program ? From the first moment you turn your computer on, you should have a trusted anti virus program by your side. Even if you have a machine that isn?t hooked up to the Internet, a reliable anti virus program is a low cost and common sense addition to any machine. There are even free anti virus programs you can download that work almost as well as industry giants like Norton, Kaspersky, Bitdefender and McAfee.
2. Install anti-spyware and anti-malware programs ? As good as the best anti virus programs are, they sometimes need a little bit of help. Thankfully, many of the top anti-spyware programs are completely free. Spybot Search and Destroy and CCleaner are just two free programs that can help prevent computer viruses from doing any damage on your machine. As helpful as these programs are, however, you must update them and run them on a regular basis for them to do any good.
3. Avoid suspicious websites ? A good virus protection program will alert you when you visit a website that attempts to install or run a program on your computer. Many less than reputable adult websites do this, so if you get a warning, don?t go back, you may end up with a bug you can?t get rid of.
4. Never Open Email Attachments Without Scanning Them First ? The most common way viruses are spread throughout the Internet is still via email. Some attachments, like pictures, now display in emails and don?t require an attachment to be manually opened, but other documents do. Make sure you use an email client that scans all email attachments before you are allowed to open them. This will help prevent computer viruses from getting a foothold on your machine.
5. Set up Automatic Scans ? Many of the top anti virus programs, as well as the best anti-spyware programs, now have settings that will let them automatically run during down times or in the middle of the night. Of course, your computer must be on for this to happen, but having daily scans run when nothing else is going on is a great way to prevent even the latest computer viruses from sticking around too long.
6. Watch Your Downloads ? Part of the fun of the Internet is downloading music, movies and other items. However, since these downloads are so massive, it can be easy to sneak a virus along for the ride. Only download these files from trusted sites that you can count on, or, at the very least, scan them before you open them.
7. Updates, Updates, Updates ? There is a reason why Windows has a feature called Critical Updates. There is an entire branch of Microsoft dedicated to staying one step ahead of the hackers out there so when they manage to fix a possible security loophole, you need to download the patch right away. Help Microsoft help you prevent computer viruses from causing too much trouble.
8. Know What To Look For ? Even if you are just a casual computer user, you should have an idea of how your machine operates, what normal pop up windows look like and what popular viruses are out there, that way, when your computer begins exhibiting tell tale signs, you?ll know. You can help prevent computer viruses by staying updated and educated.
9. Stay Away From Cracked Software ? It is so secret that you can download illegal, cracked versions of some programs online. As tempting as it may be, these files are almost always infested with advanced and difficult to detect bugs. Play it safe and get your software from the source.
10. Install a Firewall ? A firewall is a program that screens incoming Internet and network traffic. Along with your virus program, it can help prevent unauthorized access to your computer.
11. Be prepared to Lock Down ? If you hear of a virus that is spreading like wildfire through the Internet, make an extra effort to be careful. Don?t open any suspicious emails or accept any downloads for a week or two until your virus protection program has been updated and you are, once again, safe.
Top 10 Antivirus Softwares
Antivirus software is must-have protection. This review picks the best antivirus software based on its virus detection abilities, features, and breadth of protection. Whether you're seeking total system coverage or an ala carte solution, each of the following products provides superb virus protection for Windows-based PCs. Because every system is unique, evaluate several of Windows XP and Windows Vista antivirus scanners to find the software best suited for your PC and your level of experience.
1. Norton Internet Security 2009
Symantec's antivirus products have historically always provided excellent detection and removal of malware. On the downside, that protection came at the price of often crippling system performance. That's now a thing of the past. Performance overhauls are the hallmark of Norton Internet Security 2009, which features 'pulse updates' to deliver more frequent and thus smaller signature updates, whitelisting to streamline scan times, and a lighter, sleeker footprint that installs in mere minutes.
2. Avira AntiVir PersonalEdition Premium
AntiVir is a consistent leader in independent antivirus tests. Avira's AntiVir PersonalEdition Premium is a low-impact, easy to use virus scanner that also the ability to make an antivirus rescue CD for your system. Also includes WebGuard to protect against malicious or compromised websites. Five euros of each purchase is automatically donated to the Auerbach Foundation, a non-profit that supports various charity and community-related services. AntiVir PersonalEdition Premium should be used in conjunction with a firewall.
3. McAfee VirusScan Plus
McAfee VirusScan Plus is an ideal candidate for those seeking an antivirus/firewall combination without all the bloat of traditional Internet security suites. McAfee VirusScan Plus makes an easy job of removing adware and spyware, something not all antivirus products deliver. SiteAdvisor service is including, helping to guard against malicious websites.
4. Kaspersky Anti-Virus Personal
Kaspersky Anti-Virus Personal offers excellent antivirus protection, perhaps unsurpassed in its ability to unpack and scan compressed files - something that trips up a lot of other vendors. Should be used in conjunction with a firewall.
5. Panda Antivirus Pro 2009
Panda Antivirus Pro 2009 combines antivirus, antispyware, antiphishing and a firewall with its highly touted behavior-based TruPrevent Technology. License covers use on up to three computers and includes free tech support via email (telephone support options are also available).
6. BitDefender Antivirus Plus
Softwin's BitDefender Professional protects against viruses, spyware, and instant messaging threats, as well as offering firewall rules to block undesirable traffic and a privacy gateway to keep your identity and preferences private while surfing the Internet.
7. Eset Nod32
Nod32 features a small footprint, low performance hit, and fast scan speeds, providing focused virus protection ideal for gamers or those with an older PC. Should be used in conjunction with a firewall.
8. AVG Anti-Malware
AVG Anti-Malware combines traditional virus protection with adware and spyware scanning, in a low impact footprint ideal for resource-strained PCs or those who just want the best performance possible out of their computers. Free tech support is available via email and the standard license includes two years of protection. Should be used in conjunction with a firewall.
9. G Data AntiVirusKit (AVK)
AntiVirusKit (AVK) provides a double layer of protection, bundling two of the best antivirus engines - Kaspersky and BitDefender - under a single, easy-to-use console. You'll want to bolster G Data's AVK with a firewall.
10. F-PROT Antivirus
F-PROT Antivirus for Windows offers a feature that's increasingly harder to find - it includes a command-line scanner that can be used to create a rescue CD for scanning the system in Safe Mode. This is a particularly effective way to remove stubborn resuscitators. Firewall not included.
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