There’s no strict definition for a computer virus. In 1980s, the word “virus” was used for the first time to define software that was, like its biological counterparts, able to replicate and do harm to files and computers. Today, any type of malware could be named a virus, however, Trojans often do not replicate and are not classified as viruses by some sources. Also, any software aimed at protecting users from malware can be named an antivirus while, in fact, it employs a wider range of means to protect computers and gadgets from any type of attack.

It is generally considered that viruses have been created as a form of digital vandalism, and have become more profit-oriented later, when they were used for pinpoint attacks – e.g., to attack a business competitor. To this day, viruses are used in all types of attacks – except that most of today’s cybercriminals are inclined to make money instead of damaging the systems. This is why viruses today comprise just a part of the larger class of harmful software – the malware. However, the number of viruses grows steadily every year, and any Internet user has to have certain means of protection.

Viruses can spread themselves through a variety of means, including websites, e-mails, documents like Word or Excel files and removable storage devices – including, but not limited to, Flash drives, photo cameras, iPods and smartphones that could be connected to a computer. To prevent infection, use antivirus software and always keep your applications up to date.