Antivirus and firewalls have very different, and necessary functions.
Antivirus software detects and removes viruses, worms, bots and other malware from your computer. All of the above can get into your computer by multiple means – similar to viruses in humans, they are spread through contact – sharing USB devices with an infected computer, opening emails that have strange subjects / attachments and downloading files from the internet.
A firewall prevents malware and other internet hacker attacks from reaching your computer in the first place. It’s your computer’s first line of defence. A firewall creates a filter between your network and the internet. Before anything can go through this barrier, the firewall must determine whether the information being received meets your company’s security settings. If it fails to meet these security rules, the firewall will deny it access to your network.