How Do Viruses And Other "Crap" Get On My Computer?

One of the most asked questions I get when I work at a customer's computer is "I am very careful when I am on the Internet. How do these viruses then get on my computer?".

Today I found a pretty good article that answers this question in quite some depth. Before I give you the link to this article let me mention that no matter how careful you are your computer will eventually get "nailed" by some malicious software; it's unavoidable.

Last year a significant number of web servers have been cracked by hackers and infected with very tricky software that will attempt to infect EVERY visitor of any of the web sites stored on the web server. This infection is really deeply rooted; "disinfecting" the computer would disable the server and thus all web sites stored on this computer for several days. So it gets done only very slowly - if at all.

With this background in mind you may want to read this article if you want an answer to the title question.

Update Oct.27th, 2013:
The newest epidemic in malicious software are PuPs, potentially unwanted programs. The "poyenyially" is nothing but a law suit safe euphemism; you don't want any of this stuff on your computer. Please read this post for more details. 

As usual I welcome suggestions and comments right here in the blog.

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