Cybercriminals focus on cryptocurrency like Bitcoin because there is significant monetary value involved, with the total market cap exceeding $11 billion. They are able to earn coins through malware that mines cryptocurrency on victims' devices without their knowledge, or through ransomware attacks where victims' data is encrypted until a ransom is paid in cryptocurrency. Common attacks include malware containing cryptocurrency mining tools, ransomware like the WannaCry attack of May 2017 that demanded Bitcoin payments, and fake initial coin offerings that trick investors.