A worm is like a virus—it also replicates itself. However, it can stand on its own and does not need another program to run.

It usually infects your computer’s networking features, which includes its internet connection.

Spyware and adware go hand-in-hand. Spyware is a kind of program which gathers information, specifically browsing habits. It tracks down what kind of sites you visit, and adware will generate ads that fit with your interest which spyware based on information it gathered in first place.

Malware is malicious software. It’s any program that is useless, or worse, destructive.

A Trojan a program pretending to be good but once it’s deep in your system it proves to be quite opposite

In spite of all their differences, they have one thing in common: they are out to give you headaches by rendering your computer unusable

To protect your computer as much as possible from being infected, here are four dangerous activities that you should avoid, or at least minimize

Opening email attachments: Do not open any email attachments if they aren’t scanned by antivirus software. Worms can spread through email, so even a friend can unwittingly send you one by way of an attachment.

Internet File-sharing In file-sharing via internet, your computer is exposed and open to others it is communicating with. If other computers’ files can be transferred to yours, same thing can be said about a virus, if others are infected.

Downloading free software of questionable origins. Free software is free for a reason.

Their compactness, and portability makes laptop particularly useful to professional, person on go, and student. However, laptops can get rather expensive so you should take care to choose a laptop with right amount of features, but not so many that they needlessly inflate price.

Here are 9 basic features that you should consider before you purchase your next laptop:

1. Weight and Size: When it comes to weight and size, you should consider that bigger a laptop is, heavier it is. A small enough size should be chosen, but not so small that it's uncomfortable. The smaller laptop, more awkward it will be to type on that tiny keyboard.

2. Display: The display, or screen is directly tied in to size of laptop. You should choose biggest display possible. Also, a decision has to be made between Active, and Passive Matrix.

Active Matrix is more expensive, but is recommended since pictures come out sharper and moving images play out smoother. Passive Matrix is cheaper, but picture quality is not as good.

3. Batteries: There are 3 main types of Batteries. They are Li, NiMH, NiCad. What those letters stand for is not important. All you need to know is to always choose Li since they are higher quality, and provide a longer life. However, they are slightly more expensive. If one is strapped for money, then NiMH is acceptable. They're slightly cheaper, but must be recharged every hour or so. Under no circumstances should NiCad be chosen. They're extremely low quality, and have no staying power.

4. Hard-Drive: Most laptops start with at least 4.3 gigabytes, or GB, of hard drive space. However, you can get more hard-drive space if you think you’ll need it.