There are zillions of threats, from minimal nuisances to severe Malware that can completely and permanently disable vital functions to where the entire operating system needs to be reinstalled and all programs and data lost.

What is Malware: Malware is short for malicious code software (mal-ware), which includes any and all forms of code designed with malicious intent. Malware is the umbrella under which all security dangers exist, such as viruses, worms, spyware, phishing, adware, tracking cookies and rootkits.

Viruses: Threat Level - Intermediate to Severe. What is a computer virus? A computer virus is a malicious code that adds itself to other programs that exist on the computer (host), including operating systems. Many computer viruses spread quickly and wreck havoc on the system host, including potential destruction of operating systems and data.

There are different types of viruses and they range from being a nuisance that constantly displays pop-ups to severe dangers that delete system files, attach to registries, destroy the users ability to log into the Internet and even destroying the computers operating system along with all the data that is on it. Unless you have completely backed-up the data on your PC, recovering that data will be impossible if you have to re-install the operating system after a virus infection.

While there are many different viruses, the Trojan Horse is one of the most severe and all though threat severity levels vary within the different types of Trojans, basically they are all dangerous and should always be protected against. Unfortunately some Trojans infect computers and cause such damage that it becomes irreversible and a reinstall of the entire operating system becomes necessary.

The best protection against computer viruses is prevention, early detection and removal. A good anti-virus or Malware security software can protect your computers and provide peace of mind when surfing the net.

P2P File Sharing and Virus Dangers: One of the easiest ways to get a virus is by downloading unsafe freeware, shareware or person 2 person (P2P) from file sharing sites. Specifically those sites that provide P2P free music downloads. Some of these sites are Limewire, Bearshare and Morpheus. Users create a free account on these sites, download the software (which is sometimes full of Spyware/Adware on its own) and get access to millions of other peoples files through what is called the Gnutella Network. Users can search for MP3 music files and download them from other peoples computers through this Network.

First, this is illegal, but thats a whole other topic. With these types of downloads there is no way of knowing what is actually on these files and it is easy to download a serious viruses and especially a Trojan. These P2P sites should be avoided to ensure computer security. For a few bucks you can get legal and safe music downloads at sites like Napster and Rhapsody. Play it safe, paying the few bucks is well worth it, as it can save lots of money, not to mention the hassle of having to fix a damaged computer.

Worms: Threat Level - Severe. A computer Worm is a a type of especially nasty Malware that is a self-replicating computer program, which at one point almost brought the entire Internet to its knees. Unlike a virus, it doesnt attach itself to an existing program and does not infect computer files, instead it wrecks havoc on systems as it creates endless copies of itself, with the goal of taking up as much space as possible on the PC and creating program problems.

Worms almost always cause harm to the network, if only by consuming bandwidth, whereas viruses almost always corrupt or modify files on a targeted computer. Internet worms are most prevalent today in the form of email attachments. Two of the worst worms ever were Mydoom and Morris.

Worms are usually sent via email by attachments, you should never open an attachment in your email from an unknown source. Also, when deciding on an anti virus security program it is important to make sure that the email scanner is activated and that the software covers protection, detection and removal features for worms.

Spyware: Threat Level - Low to Severe. Spyware is one of the most common types of Malware and often slows computer performance. Spyware spies on your web browsing activities and comes in forms of keyloggers (where your keystrokes are monitored), recording/sending your web browsing habits to a third party, causing unwanted pop-up adds, hijacking home/search pages and making changes to them, as well as, redirecting browsing results.

A Spyware infection can be caught in several ways. One way is by clicking on a bad link from a bad site. Two, through small windows of advertising that pop up during web browsing (pop-ups). Third, there is what is called a drive-by type download and that is where Spyware infects computers without the user noticing, just by visiting a bad web page. Tip: All web browsers allow you to check a block pop-ups selection which can be accessed from the browser toolbar under options.

Adware: Threat Level: Low to Intermediate. Adware is Advertising Display Software that delivers ads in a manner or context that is unexpected, unsolicited and automatically loaded. Many adware applications also perform tracking functions, and therefore may also be categorized as Tracking Technologies. Adware causes pop-up windows with advertisements in the browser based on the information it collects from the users browsing patterns. Sometimes adware may be installed in conjunction with a companion Spyware program.

Phishing: Threat Level - Severe. Phishing is a form of Internet fraud that aims at identity theft. Its purpose is to steal valuable information such as credit cards, social security numbers, user IDs and passwords.

A phishing site is a duplicate of a legitimate site and it is created to dupe users into logging in and therefore stealing private information. Many phishing scams are perpetrated via mass emails which alert the customer to some problem with your customer account or some other hook, usually from a bank, or Paypal or some other institution and it lures people into entering their private data by following a link to the phishing site of a real site.

The recent IRS rebates spawned a phishing scam, where mass emails were sent with IRS logos informing taxpayers that they are due a rebate check but they must first follow the IRS link and input their information to receive the rebate. The link, of course, leads to a phishing site where unsuspecting people enter personal information, like social security numbers which are then hijacked by identity thieves.

It is important to realize that most reputable companies do not usually send emails soliciting private data. In fact, Paypal explicitly lets its users know that they never solicit customers via email in any way. The IRS has a fraud alert on their homepage advising taxpayers of such phishing scams. If you get emails like this just hit the SPAM button and run for your life or at the very least check with the institution that sent the email in some other way.

There is also the danger of running into a phishing site while web browsing, it is important to have computer security software that will alert to phishing sites with real-time protection.

Phishing security is NOT standard on all anti virus software and Malware removal programs. When considering a security program make sure to look for phishing protection.

Drive-By Downloads: Threat Level - Low to Severe

Drive-By download is where all types of Malware can infect your computer via a visit to a web page. The Malware codes are embedded in these bad sites and looks for users computers to become hosts to attach itself to. It is important to look for drive-by or real time protection when considering security software. Drive-by or real time protection should be included on the anti virus software that is on the computer.

Rootkits: Threat Level - Severe. Rootkits are really bad because they can hide their existence from operating systems and users and cause major destruction. Because Rootkits create stealth program codes that run at a lower level than can be detected with all normal anti virus software and Malware removal programs, it is crucial to make sure that the security software explicitly protects against rootkits.

Cookies: Threat Level - Low. Some cookies are positive and really do not harm to your system in anyway, they simply temporarily store your log-in information so that you do not have to enter it again when you return to that site. Plus, many sites will not run properly without cookies enabled and so they are a necessary element. And these temporary cookies can be cleared from within your browser at any time you.

On the other hand Tracking Cookies are a form of Tracking Technology. Tracking Cookies are used to track the surfing habits of users in order to manage, analyze advertising data, and they may be used with the more malicious intent of monitoring user activity more closely. Tracking cookies are usually easily detected and protection from them comes standard on most anti virus and Malware security software.

It can be more difficult to remove Malware if infection occurs than to protect against it and some Malware causes such damage that a complete operating system reinstall is required.

There are many Malware security softwares, including some great free ones, and firewalls, that offer various levels of protection. It is important to have a complete suite that protects from all Malware dangers.