It also blocks malicious URLs and uses behavior-based detection to ward off potential threats. Although it has no configurations of any kind, you can expect it to automatically scan your computer in the background with the use of cloud-based detection, subsequently running a deeper scan if it discovers any malicious software or red flags. The Bitdefender Antivirus Free Edition features a minimalist design, which makes it low-maintenance. This cloud-based antivirus software pinpoints suspicious files, ensures real-time malware removal, does quick and instant Cloud-based scanning, immediately updates on the new and up-to-date virus definitions, has a user-friendly interface and offers automatic scanning of files as and when they are downloaded from the internet. Comodo Internet Security (CIS) is the number one free antivirus for military members, particularly because of its features, such as Auto-Sandboxing Technology, Default Deny Protection, Cloud Based Behavior Analysis, Cloud-Based Whitelisting, One-Click Virus Scanning, and more.