Antivirus products have been available to computers users for a quite some time. Many companies have produced different antivirus firewall software applications for users. Antivirus software helps you in removing viruses and preventing them from infecting your system. Antivirus programs are used to detect, identify and delete viruses, malware, trojans, and worms when they enters your network or local computer. Antivirus software is fashioned to protect your computers, but you still need to purchase it. At present, there are lots of choices of antivirus programs which are produced by different companies. The most common antivirus programs today are Avast! Antivirus, AVG Antivirus, Avira Antivirus, BitDefender, ClamWin, ESET NOD32, Kaspersky Antivirus, McAfee Antivirus, Panda Antivirus, and Symantec Norton Antivirus. It is strongly recommended that computer users should install antivirus programs in their systems. However, in choosing which version to install, you need to know the pros and cons. There are free antivirus programs available. They are really free to download.  However, installing free antivirus programs has its disadvantages. Not all free antivirus products are updated. Thus, most of the time, free antivirus software cannot recognize, detect, and identify new viruses and malware.  The databases are not updated in some of the free versions of antivirus products. Aside from free versions of antivirus software, there is also the trial version of antivirus products. Trial versions are made so that users can evaluate the products. Trial versions of antivirus products are more updated than free versions of antivirus software. However, trial versions of antivirus software usually last for 30 days only. Thus, you need to download another antivirus product or purchase the licensed version of that antivirus software. On the other hand, licensed versions of antivirus software are considered the most effective of the three versions. Although they are effective, they come with a price. There are people, though, who cannot purchase the licensed version so they stick with the free and trial versions. Licensed versions entail more complete protection and are easy to update. They have more benefits than the other two versions like updated databases and strict security. Moreover, licensed versions have more tools for protecting your computer than free versions and trial versions have. In choosing an antivirus firewall software solution for your computer, it is important for you to understand the pros and cons of choosing either a free version, a trial version, or a licensed version of the program that you wish to use.