What is a computer virus?
A computer virus or malware is a commonly used term to describe all types of malicious software including Trojans, worms, adware, and spyware. Each have slightly different functions, but usually either try and damage the software on your computer, or send information about your computer usage to an outside source over the internet. The details of each type are explained below:
Types of computer viruses:
Trojans: A Trojan, as the name suggests, pretends to be something good, like virus scanning software or other useful applications. In reality they run malicious programs in the background that can perform any number of functions, like allowing an outside user to copy your files, see your browsing history, or even take remote control of your computer.
Worms: A computer worm is a self-replicating computer program. It uses a network to send copies of itself to other computers on the network, and it may do so without any user intervention. Unlike a virus, it does not need to attach itself to an existing program. Worms almost always cause at least some harm to the network, if only by consuming bandwidth, whereas viruses almost always corrupt or devour files on a targeted computer.
Adware: Adware or advertising-supported software is any software package which automatically plays, displays, or downloads advertisements to a computer after the software is installed on it or while the application is being used. Adware is usually seen by the developer as a way to recover development costs, and in some cases it may allow the software to be provided to the user free of charge or at a reduced price. As a result, the advertisements may be seen by the user as interruptions, annoyances or as distractions from the task at hand.
Spyware: Spyware is computer software that is unknowingly installed on a personal computer to collect information about a user, their computer or browsing habits without the user's informed consent. Spyware programs can collect various types of personal information, such as Internet surfing habits and sites that have been visited, but can also interfere with user control of the computer in other ways, such as installing additional software and redirecting Web browser activity. Spyware is known to change computer settings, resulting in slow connection speeds, different home pages, and/or loss of Internet or functionality of other programs
How can my computer be infected?
Unfortunately, there are many ways your computer can become infected. Some of the main causes to an infected computer included: illegally downloading music and movies, clicking on ads, browsing to compromised websites, and in general not being cautious when it comes to web browsing.
What are the symptoms of a virus?
There is a wide variety of virus symptoms that differ based on what type of infection you have and how far the virus has progressed. A list of common symptoms is listed below:
- Speed decrease
- Unexplained freezing/crashing
- Programs that won’t launch
- New programs won’t install
- Computer has trouble booting windows
- Internet access is blocked (completely or certain sites)
- Desktop/appearance/screen saver and other visual settings are changed unexpectedly
- Unable to open files or folders
- Files or folders are deleted unexpectedly
- False pop-ups that appear warning you about viruses
- Deteriorating condition over a period of a few days to a few weeks (viruses that download more malicious software as time goes on)
- Unable to print documents
- Your hard disk runs out of free space (this comes from an infected file making copies of itself)
How can I protect myself?
- Keep your computer's operating system up to date using Windows Update or Software Update on Mac.
- Install anti-virus software on your computer.
- NEVER use file sharing programs to download games, music, movies, TV shows, etc. A large majority of the files shared on this network are infected.
- NEVER click advertisements on the Internet.
- NEVER give anyone your password.
- NEVER respond to SPAM.
- READ all warnings very carefully.
- EDUCATE yourself, your friends and family about infections.
How to protect your computer:
- Don't open suspicious e-mails.
- Scan your computer for viruses on a regular basis, such as once per week.
- Create a strong password .
- Back up important data.
- Install the latest updates to the software you use, such as your web browser, Microsoft Office, etc. If your software does not automatically download updates for you, check the developer's website to be sure you're running the latest version.
- Anti-Virus protection.
- Being aware of what you are doing.
- Regularly updating your Anti-Virus definitions.
- Regularly scanning your computer for infections.
- Keeping your computer up to date with system updates.
Why should I do it?
- Keeps your computer functional.
- Makes things easier in the long run (preventive maintenance).
- Keeps your personal information safe and secure.
- May put less stress on your computer and keep it running better, longer.
Ways to be aware:
- Look at emails before replying to them. Check the spelling and punctuation for errors. Many times phishing emails will have simple errors that are easy to see.
- Be aware of emails asking for personal information, generally a real organization will make you change your password/login yourself, rather than asking you for yours.
- If there is a program that pops up on your computer saying that you have viruses, and you did not install that program, then it is a virus. Also be cautious of web-pages that have similar pop-ups that are not part of your computer.
- When you visit web-pages, look for the content you intend to find, not what is flashing, or ads on the side.
How can I scan and remove a virus infection?
The first order of business is to get anti-virus software. It is also recommended that you download other virus scanning tools, like Malwarebytes which is available for free.
After obtaining the software simply run the program and have it scan for viruses. A good habit to exercise before each scan is to double check that the software's definitions are up-to-date. In order to update the definitions there should be either a tab or button that relates to updating the software, e.g. "Check for Updates online."