I am pretty sure about this fact, that if I will ask this question; most of the people would say, "NO, We don't have an antivirus! Do we really need it?". And my friends from India and other asian countries, I can't even expect people to have genuine copies of their operating systems. This is a shame on us. You are purchasing the hardwares but not the softwares! You are using carcked or pirated versions. If you think this is not a crime, just sit and think again, if you would have not purchased your PC or Lap Top but have jumped inside the store took the PC or the Laptop and just have ran away. Will this be a crime? Of course the reply would be positive this time.
Your machines (Hardwares) need quality softwares to make full utilization of your system. Always make sure that you purchase a genuine copy of Operating System. And if you are not using an antivirus, your computer may get down, it may get crashed, it may stop working or it may start producing unexpected and annoying results.
If you won't have an antivirus software, your files may get corrupted, your softwares might stop working and you might face a point when your system will stop responding. Always avoid such situations to come. Please purchase a good Anti-Virus software. An anti-virus software will protect your system from viruses, trojans and other such harm ful programs. I would personally recommend you to purchase Norton. In my opinion it works really well to protect your PC. There are many more anti-viruses available. I would not take name of other softwares because in my opinion it is the best one.