Ransomware is a complex class of malware that blocks access to files and holds that data hostage until you paid the ransom.
Attackers often use many tricks to sneak ransomware to your systems such as social engineering, malware advertisement, third-party apps, and other threat vectors.
The most significant ransomware attack to date, WannaCry, used the EternalBlue exploit to infect more than 300,000 victims in over 150 countries.
Ransomware-as-a-service is booming. Some cybercriminals now allow other hackers to use their ransomware in exchange for a cut of the resulting ransom.