Ransomware is a type of malware that restricts access to the infected computer system, and demands that the user pay a ransom to the malware operators to remove the restriction. Some forms of ransomware systematically encrypt files on the system's hard drive, then spread to any shared network drives and other computers, and make it difficult or impossible to decrypt without paying the ransom for the encryptionkey. Other forms of Ransomware may simply lock the system anddisplay messages intended to coax the user into paying to acquire the key. Ransomware typically propagates as a trojan, whose payload is disguised as a seemingly legitimate file.