Antivirus on one's computer is very necessary. And most, if one is accessing the internet every now and then. Viruses like worms and trojans go along with some opened and viewed files. If one does not have an antivirus installed, there is the tendency for the connection to slow down and worst of all, the computer may just bog down.
The antivirus in my computer have always detected worms. Recently it detected a trojan virus in the game downloaded by my son. I had the file contaminated with trojan virus deleted. But i can't be so sure if the virus is still in some of my files. I need to have my computer reformatted as i noticed lately that it is slowing down. Plus, i need to update the antivirus as something keeps on popping up that my antivirus is blacklisted already.