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What's a virus? - A computer virus is malicious software that is almost always developed by programmers linked in some way to the criminal world.

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How do they work? - Like a biological virus, computer viruses infect a system, multiply and spread on to other computing devices.

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Infection - Infection can occur in several ways, including downloading infected files, infected email attachments, accessing malicious websites access, using infected pen drives, and any other data storage devices.

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The first virus - The first computer virus in the world was called 'Creeper virus' and was detected on the 1970s internet network ARPANET. The virus was developed by Bob Thomas in 1971.

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Types of viruses - There are currently three categories of computer threats: viruses, worms, and Trojans. They are different in behavior, but they are all built from the same basic principle.

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Organized crime - It is believed that about 70% of virus programmers work for organized crime groups.

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Very powerful virus - The Melissa virus, released in 1999, was so powerful and hard to destroy that Microsoft and other large companies had to completely shut down their email systems until the virus was completely eliminated.

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Before the internet - Before computer networks were the norm, most of the viruses were spread by diskettes. In the days of the first personal computers, many programs and information was passed between systems using diskettes.

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Is your computer infected? - According to Microsoft's latest security report, an estimated 40% of personal computers in the United States have some kind of virus.

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Law - Programming computer viruses is not illegal in countries such as the United States, however, in Finland it is seen as an act punishable by law.

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Types of crimes - Nowadays, crimes involving computing devices are recognized all over the world and divided into several categories, including cyber terrorism, cyber extortion, and even cyberwarfare.

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New viruses - It is estimated that around 6,000 new computer viruses are created each month.

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And before? - In 1990 there were only about 50 computer viruses.

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Emails and viruses - Contrary to popular belief, it is not possible to get infected just by opening and reading an email. For the virus to infect your computer, you must click on a link or download an infected attachment.

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Strategy - Facebook pays about $500 to anyone who can hack their website and find vulnerabilities in the system.

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Antivirus - There is currently no antivirus software that can detect and eliminate all viruses circulating on the internet.

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Damage - Every year, computer viruses are estimated to cause millions of dollars in economic damage due to system failures, data corruption, and maintenance costs.

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Programs - It is estimated that 1 in 14 downloaded programs come with some form of malicious software.

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Update your computer - An updated operating system is a great way to avoid becoming infected with viruses and being hacked. If your computer is out of date, it becomes more vulnerable. Make sure you install all updates.

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Update all programs - The same goes for old and outdated programs. They may be vulnerable to malicious attacks. If they are up-to-date, your computer will be better protected.

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Copyright infringement - Is it really worth it to download the latest movie instead of going the movie theater? Often, these files are infected with malicious software.

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Be careful with what you click on - If you're suspicious about a link or file sent to you by email, Facebook, or any other medium, don't click on it. Curiosity killed the cat and it may also kill your computer.

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Different passwords - Are you one of those people who has the same password for all of their accounts? Stop doing that, use different variations. Malicious software just needs to find your password once to have access to everything about you.

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Avoid clicking on filename extensions ‘.exe’ and ‘.scr’ - Files ending with '.exe' means that they are executable files. So, if you download a movie with this extension, do not open it!

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And how about ‘.scr’ ? - If a file ending in '.scr' refers to a screen saver, it is often just to confuse the user. Avoid clicking on it.

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Do backups - Regularly backing up your most important files, whether in a pen or using a cloud, is a good way to prevent anything that is most essential to you from becoming infected.

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Computer health check - Are you regularly aware of you system's health? Has this gallery helped you to figure out what you need to do to keep your computer safe?

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