Although Microsoft says that their latest operating system, Windows Vista, is more secure than their previous operating systems, but we still need to install other security softwares to enhance the protection.
If you don’t have money to spend to buy security applications for your Windows Vista, here I will share with you free security softwares that you can use for your system. No money is required but you still need to pay for your internet subscription. 
I have divided this entry into three sections, Antivirus, Firewall and Anti-Spyware. You can click on the page number below to go through the sections. 
ANTIVIRUS
AVG Antivirus [ Website | Download ]
AVG is a well known free antivirus solution to computer users. It is not only free-of-charge, it is also easy to use and not slow your computer down.
Features:
- Automatic update functionality
- The AVG Resident Shield, which provides real-time protection as files are opened and programs are run
- The AVG E-mail Scanner, which protects your e-mail
- The AVG On-Demand Scanner, which allows the user to perform scheduled and manual tests
- The AVG heueristic analysing monitor
- Free Virus Database Updates for the lifetime of the product
- AVG Virus Vault for safe handling of infected files
