Which free antivirus softwares for your PC?

I have tried use some commercial softwares and free softwares, I see that a normal user can rest assured that a free antivirus softwares are well able to protect his PC. Those softwares solve most security problems. You may use a commercial software when you have high demands as update special data, support from supplier's experts, server systems,...

I am going to introduce three good free antivirus softwares which I believe that they are very effective & useful for your PC.

Avast: (download a free version)

+ Real-time scanning

+ Stable

+ Operating smoothly

+ Updating daily & automatically

+ The interface is simple and attractive

+ Antivirus & Anti-spyware

+ With a free account, you have a free key for using within a year. Avast will sent a key to your email. You open Avast window, go to Maintenance > Registration and insert free key. After a year, you sigh up another account and continues use Avast with another free key. It's very simple & fast.

+ Effect: Great!

Avira: (download a personal version)

+ Real-time scanning

+ Stable

+ Operating smoothly

+ Simple interface

+ Antivirus

+ There are some problems about update data with a free account.

+ Effect: Good!

AVG: (download a basic version)

+ Real-time scanning

+ Stable

+ Update easy.

+ Friendly interface

+ Antivirus & Anti-spyware

+ Effect: Quite good!

Everything success with you.