Incorporated with advanced encryption algorithms, this type of ransomware is designed to block system files and demand payment to provide the affected user with the key that will decrypt the blocked content. For example: Crypto Locker, Wannacry, Locky, CrytpoWall, etc.
This malware locks the person out of the OS, making it impossible for them to access the data saved on it. Here, the files are not encrypted, but the ransomware still asks for a ransom to unlock the infected device. For example: Police-themed ransomware or Win locker.
Master Boot Record (MBR) ransomware is a type of Locker ransomware. The MBR is a section of a hard drive that enables the Operating System to boot up. However, when the MBR ransomware attacks the drive, the boot process fails to complete and demands the payment of ransom as soon as possible. For example: Satana, Petya, etc.