A virus is malicious in nature and will delete files and/or cause damage to your computer often forcing you to reinstall your operating system. A virus is usually designed to spread and to cause as much damage as possible before Anti-Virus software is able to detect and remove it. Viruses often disguise themselves as desirable files and need human interaction to execute.
What is a Trojan or Trojan Horse?
A Trojan is a program that installs malicious software under the guise of doing something else. For example, Free Games or Free Screensavers also come bundled with a Trojan. These Trojans can do things like log your keystrokes to steal your passwords, or install a backdoor on your computer that would allow someone to connect to it. Trojans are not usually designed to spread rapidly like a Virus or Worm.
What is a Worm?
A worm spreads by exploiting vulnerabilities in an operating system. This is why it is very important you always apply operating system updates as they come out. Worms are self replicating and designed to spread rapidly. Worms are often used to exploit the operating system and then install some type of backdoor or remote control mechanism on the infected computer. Worms also always harm the network by consuming bandwidth.
What is Malware/Spyware/Adware?
Malware/Spyware/Adware all mean the same thing – it’s unwanted software that causes harm to your computer by consuming system resources, tracks your Internet activity, provides a backdoor in to your computer, and/or takes over functionality of your machine. Toolbars, screensavers, custom cursors, games, shady websites, file sharing programs, etc are all common causes of infection. Malware is similar to a Trojan in some ways.
How do I detect and remove Malware?
Anti-Spyware software is designed to remove Malware/SpyWare/AdWare from your computer. Popular free solutions are Spybot – Search and Destroy (www.safer-networking.org) and AdAware Free (www.lavasoftusa.com). There are commercial products that are not free but are also very good, such as SpySweeper from Webroot (www.webroot.com).
What is the latest trend in Malware?
The latest thing is actually fake ads that popup saying that they have detected Spyware or Malware on your computer and to click on a link to remove it. Clicking on the link takes you to another site that will either directly infect you or it will direct you to download an “anti-spyware program” that is actually Malware itself and will do nothing to help you. See the picture below for an example.
What about toolbars?
Not all toolbars are bad, however most are not very helpful and are usually annoying. If the toolbar installed is malicious (such as Hotbar or MyWaySearch) your Anti-Spyware program will remove it for you. However, if it is something like Yahoo! or Google Toolbar you will need to remove it yourself by going into Add/Remove Programs in the Control Panel.
Additionally, when installing software make sure you read the screens during installation. Many time things like Yahoo! and Google Toolbar will come bundled with other software, but have the option to opt out. For example, when installing Adobe Reader or Google Earth there are check boxes during the installer that ask if you would like to install toolbars, most people do not read the installer screens and will just click through and end up getting the toolbar.
What is Phishing?
Phishing is an attempt to steal personal informartion, financial information, or your username and password for an account by misleading a user into trusting a fraudulent email or website. Why is it called "phishing"? It's a variation of "fishing" -- as in "fishing for information." Phishing has been around since the early days of the Web, when the scam du jour was pretending to be an AOL customer service agent in order to steal account information for free Internet access. Click here to read more about Phishing
