What is the best virus software

  What is the best virus software to use. I get asked that question on a daily basis. For myself in the free category I prefer free Avast antivirus software. When I was trying to decide I took a look at a number of reviews. The Avast antivirus was rated number one in the free category. I run that In my computer and it really does perform very well. I have had a number of times where it has stopped some malicious site from infecting my computer. I would definitely recommend it to any person.
  The next two antivirus programs in the free category I would recommend are free AVG antivirus and Microsoft Security Essentials. Both of these seem to do a pretty good job. I tend to prefer the AVG before Microsoft Security Essentials. The Microsoft Security Essentials does seem to be a little less intrusive then AVG.
  The next category would be the paid versions of software. The top rated seems to be Bitdefender followed by Kaspersky. Honestly I have not used Bitdefender so I really can`t say anything about it. I have heard from others that it does a good job. I have on the other hand used Kaspersky and it does seem to do a pretty thorough job.Next in line would be Norton Antivirus. I have installed this on some machines and it does a pretty good job. A few years back it was found to use a lot of resources and slow machines down. That does not seem to be a problem with newer computers due to faster microprocessors, memory and a front side bus speed.
  As usual my advise will always be back up your data, because you never know what will happen.
  Thanks for reading and comments are always welcome.