Virus - definition:
A computer virus is a malware program that, when executed, replicates by inserting copies of itself (possibly modified) into other computer programs, data files, or the boot sector of the hard drive; when this replication succeeds, the affected areas are then said to be "infected".1234 Viruses often perform some type of harmful activity on infected hosts, such as stealing hard disk space or CPU time, accessing private information, corrupting data, displaying political or humorous messages on the user's screen, spamming their contacts, logging their keystrokes, or even rendering the computer useless. However, not all viruses carry a destructive payload or attempt to hide themselves?the defining characteristic of viruses is that they are self-replicating computer programs which install themselves without user consent.
Virus writers use social engineering and exploit detailed knowledge of security vulnerabilities to gain access to their hosts' computing resources. The vast majority of viruses target systems running Microsoft Windows,567 employing a variety of mechanisms to infect new hosts,8 and often using complex anti-detection/stealth strategies to evade antivirus software.9101112 Motives for creating viruses can include seeking profit, desire to send a political message, personal amusement, to demonstrate that a vulnerability exists in software, for sabotage and denial of service, or simply because they wish to explore artificial life and evolutionary algorithms.13
Computer viruses currently cause billions of dollars' worth of economic damage each year,14 due to causing system failure, wasting computer resources, corrupting data, increasing maintenance costs, etc. In response, free, open-source antivirus tools have been developed, and an industry of antivirus software has cropped up, selling or freely distributing virus protection to users of various operating systems.15 Even though no currently existing antivirus software is able to uncover all computer viruses (especially new ones), computer security researchers are actively searching for new ways to enable antivirus solutions to more effectively detect emerging viruses, before they have already become widely distributed.16
Sick computer - what can you do?
You should keep your computer safe. What do You really know about viruses? If You think they are not dangerous, you are in a big mistake. In fact, computer virus can destroy all your data, but damage could be worse. What can you do when your computer gets infected? First try to use an antivirus program to scan your disk, it is still possible to remove a problem. What if it will not work?
In the worst case, call for help to a computer service - they will know what to do to fix your computer and save your files.
Fix or buy a new one? Fix!
Failures of laptops happen quite often. The reason is prosaic - the laptop is a portable device, so it is quite fragile and it can be easily damaged by an accident. Child or dog can drop it from the desktop or the couch - if you're unlucky, the screen may break. Does this mean that you have to buy a new computer? Absolutely not! You should take your broken laptop to the trusted computer service, or you can check if the warranty does cover this type of failure. Do not panic - you can always find a solution that will not ruin your wallet.