Types of cryptocurrency According to some estimates there are perhaps as many as different varieties of cryptocurrency available for purchase on the world market today, but at our Bitcoin ATM locations in Cleveland, RockItCoin gives you access to what we think are the most reliable forms of the cryptocurrency. Bitcoin differs from traditional currencies because it is decentralized, as a group of volunteer coders maintain it. Keep in mind that Bitcoin transactions cannot be reversed, but this is a good thing in the sense that your transactions will not be tampered with.