Like the name suggests, ransomware is the digital equivalent of a hostage situation. Hackers use ransomware to encrypt the personal files on your computer or phone, preventing you from accessing them until you — you guessed it — pay a ransom. Avast Free Antivirus blocks ransomware before it can get anywhere near your files — let alone encrypt them. And don’t worry about accessing and using all of your files (documents, photos, etc.) as you normally would; ransomware protection works quietly in the background.