Having worked on hundreds of customer computers over the past 4 years i found that even with anti virus software it is possible to get virus's. I've seen computers with free versions and full subscription versions of many programs that still allowed computer virus's through. Just to name a few: Norton, McAfee, Kaspersky, Panda, Eset, Avast, AVG, Avira. Many of these programs hog resources as well and can slow down a computer tremendously from what i have seen. Check your processes in task manager, imagine if you could have the extra resources from these programs and still not get a virus. Well you can! I have now been using my computer for over a year without a antivirus program and I am still free of virus's.
I have found you can get a virus by:
1. Clicking Ad's on websites
When i say this, i mean Ad's that link to pages you are unfamiliar with. Not Ad's for like google.com, target.com etc. These Ad's will link to strange websites that you have never been to before. Ex: freecashnow.com or something similar. These Ad's can appear misleading in nature as well. They will say, fill out this survey to win this, or Get 70% off Apple IPad, blah blah blah BULLSHIT! Many of these sites have computer virus's on them just waiting to infect your computer!
2. Clicking on unknown websites from search engines.
Similar to the Ad's, although somewhat harder to deal with. I understand that you are trying to find what you are looking for, but if the URL of the page looks odd, chance are it is!
3. Pornography Websites
Not all pornography websites have virus's on them but there are millions of pages that do. If you go web searching for porn sites and get all click happy, you are guaranteed to get a virus. GUARANTEED! Just dont look at porn, is that so hard?
4. Downloading Illegal/Unknown Files
Files from unknown emails, p2p programs like limewire, torrents, downloads from random ass websites. Just dont download illegal files. Stay away from limewire and torrents. You are downloading ILLEGAL material anyways. You shouldn't be doing this in the first place.
Besides staying away from these 4 virus happy places, there are a few other thing you should do..
1. Dont use Internet Explorer, Use Firefox!
The other browsers are better and safer than IE as well, but Firefox is needed for the add ons. Plus its a great browser!
2. Install the Firefox add on, Adblock Plus
Just go to tools/addons and search for it there. This add on will eliminate nearly all ads on websites and videos, and result in faster page load times.
3. Install the Firefox add on, WebOfTrust
This addon will show a rating next to search engine results. Green = page is safe, Red = Avoid.
Now the rating system is based on user reviews, it is not perfect but it is damn good. A million times safer than searching without it!
4. Use windows update
It is there for a reason! Keeps your OS up to date and secure. Should be run at least once a month or automatically.
And that is it! This is all i have been doing for over a year and guess what, No virus's! No antivirus software! Fast computer! :3