Working on with high end gaming computers most of my life I have labeled myself as a resident computer expert. One of the most common questions I get is "what's the best antivirus software available"? While I do have a few recommendations for this I must first say one thing. YOU are the best antivirus protection your computer has. Browsing the net safely, being careful of emails you open and files you download are the best recommendations I can give. Generally I don't run any antivirus software on my system because I am careful. But for the average user you may still want to be protected.
Here are a few of my favorite utilities in no particular order:
Panda Antivirus I first started using this software when it was free and in beta. I was instantly attracted to the software because it used the principals of cloud networking to combat a virus. If a user gets a virus it is automatically quarantined and all other users logs are updated to block the virus. This allows the software to block viruses at a constant rate rather than relying on index updated that may only come out every few months. This has both a free and paid version.
AVG A good all around antivirus software that is the factory choice by many manufacturers. Not going to go into a lot of detail on AVG since its quality depends on the version you choose.
Malwarebytes Not necessarily just for virus protection, Malwarebytes is a great free application that has proven to be a must have tool in infection defense. I usually run the quick scan. If nothing is found I will just do that. If I do find an issue I run the full scan which only takes a few hours depending on your hard drive capacity. This is free and works extremely well.
ESET Antivirus protection similar to others except for one thing. This software is made for computer gaming enthusiasts. It maximizes system performance and reduces lag while gaming.
Norton Internet Security While having badass commercials, they also have a bad ass product. This features user intervention to protect your system from common scams like pop ups that con you into buying fake antivirus protection or phishing look alike sites that try to steal your account information.
At minimum you should be running a system cleaner or antivirus software. Given the following information you should be able to make a clear choice that will help ensure your system is protected.