What is a virus?
A computer virus is a fragmented or piece of executable code that can copy or replicate itself, thereby spreading itself from file to file and computer to computer. It acts much like biological viruses in humans that get passed due to proximity and/or contact which is where the name virus comes from.
Where do viruses come from?
It used to be that you needed to know computer programming to create a virus. These days there are many more people that know more about computers and with tools available on the Internet, even with minimal programming knowledge it is not hard to create your own virus. They come from confused individuals that want to harm people they don't know and even people they do know because viruses are not selective.
What do the creators of viruses get from it, does it pay?
They get to hide the fact that they created something that harms others for their entire life. They get the shame and guilt that comes with knowing in their hearts they have hurt and not helped the world. Other than that, nothing. It pays no dividends, does not further careers, gains no favors, adds no value.
How bad is it?
There are over 70,000 known computer viruses in the wild today and new viruses being created every day. This is the key reason why it is so important to get an anti-virus solution and keep it updated.
Aren't all viruses pretty much the same?
The only similarities are that they replicate and cause denial of service on some level. Newer viruses are becoming more stealthy because they are polymorphic. This means they can infect a file and change key elements in their signatures or patterns to cover up there tracks. Discovering and stopping these viruses is now even more difficult. The new viruses are getting smarter and harder to stop because people are building on the knowledge gained from past viruses. The evil men do lives long after they are gone.
How can we stop viruses?
That is a big task but it can be compared to polio. If everyone gets the medicine (anti-virus solutions) and keeps them up to date, (like a flu shot) then life for viruses would get very difficult very quickly. It is very important to get the meds and keep taking them until the viruses are gone.