Avast is one of the best free antivirus software available today. Avast was introduced way back in 1988 and it has evolved itself into a great software today.
Avast is available as both a freeware and pro versions like Avast Internet Security.It is available for both windows and Linux users and is loaded with features.The free version is perfect for Home users who use their computer systems to send e-mails and surf popular websites.It is however recommended to use the commercial Avast Internet security, if you have confidential and sensitive data on your system.
Avast 5, the current version of the free antivirus software, has an improved and state of the art antivirus and anti-spyware engine that guards your system against viruses, malware, worms and other malicious software.It also has a boot-time scanner that scans your PC for viruses and malware, before the operating system is loaded and before a virus can be activated! However, this currently works only on 32-bit operating systems.

The free avast antivirus has six different shields to guard your PC against all means by which your PC can be infected namely the web, mails, Instant messaging client, P2P software, files and network.
- File System Shield – Avast’s file System Shield scans all opened and executed files for viruses and protects your systems from getting infected
- Mail Shield – The mail shield scan all incoming and outgoing mails for malware. The email clients are protected by a generic POP3/IMAP4/SMTP proxy that also supports scanning of SSL communication through Gmail, etc.
- Web Shield – This is an important engine as it guards the PC, when you are connected to the internet, by scanning all visited web pages and checking all files, pages and java scripts downloaded from the internet. But at the same time, Avast also has the technology to ensure that you browsing speed doesn’t get slowed down
- IM Shield – This engine offers computer protection by scanning all files downloaded while using instant messaging (IM) or “chat” programs. It offers the protection for a huge list of IM clients that includes MSN Messenger, Skype, Yahoo! Messenger, Google Talk, ICQ, AIM (AOL Instant Messenger), Miranda, IM2 Messenger, Gadu-Gadu, gaim/Pidgin,Infium, mIRC,Odigo, PalTalk Messenger, Psi Jabber Client, QIP, QQ, SIM, Tlen, Trillian, WengoPhone, XFire.
- Network Shield – This engine protects against network-based viruses through an URL blocker, that is designed to block malicious URLs (as defined by the Virus Lab), and a lightweight intrusion-detection system.
- P2P Shield – This guards the PC when you use P2P software to download files. Avast can work on many P2P clients
In addition to the above shields, Avast 5 has a new Behavioral Shield that monitors all computer activity using a number of sensors i.e. file system, registry and network based sensors.These sensor blocks and reports any suspicious behavior.
The free Avast 5 antivirus software offers real time anti-rootkit protection as well! Its unique “on access” technology monitors all kernel-mode drivers that the OS on your PC is loading, for signs of rootkit behavior.
Avast 5 also has a new New Silent/Gaming Mode that automatically detects all full-screen applications and disables pop-ups and other on-screen notifications! This free software not only ensures security but it also ensures that the PC performance or the browsing performance isn’t affected through multi-threaded scanning optimization.
Free download Avast 5 from here and enjoy using the best free antivirus software on your windows or Linux computer system.
Enjoy the free antivirus software – Avast!
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