I don't think group of ISIS uses bitcoin. But the one who supported them used bitcoin to transfer the money so that it can easily transfer and it's hard to trace. bitcoin can be used in all transaction good or bad it depends on the people or group how will they used it. Also isis also use a modern technology and lot of they're work use in computer. Isis know about bitcoin but they're force to use it because it's safest way to recieve money in the organization.Bitcoin is pseudonymous, not anonymous, so it's real to connect it to real identities. Maybe it was used before because there were no alternatives but now we have Monero.Bitcoin gives a lot of advantages in every area of buying or selling different types of goods. But i think that if ISIS would use bitcoin that it would make them more easy to beat. They actually need something much more stable like a gold in a real world.Bitcoin and Altcoin are most likely to be used for crime, we all know that the excess Bitcoin and Altcoin are very supportive for use in crime, money laundering, even terrorists like ISIS. Excessive support is the delivery of coins or tokens in minutes, can not be prevented, in large numbers, the privacy of the sender and the recipient can not be known by anyone. Those things are very supportive used for crime. But we pray that things do not happen in large numbers, or maybe one day there will be developments in both Bitcoin and Altcoin in following up on those crimes.