A cryptocurrency is a digital or virtual currency that is secured by cryptography, which makes it nearly impossible to counterfeit or double-spend. Many cryptocurrencies are decentralized networks based on blockchain technology—a distributed ledger enforced by a disparate network of computers. A defining feature of cryptocurrencies is that they are generally not issued by any central authority, rendering them theoretically immune to government interference or manipulation.
Cryptocurrencies are usually built using blockchain technology. Blockchain describes the way transactions are recorded into "blocks" and time stamped. It iss a fairly complex, technical process, but the result is a digital ledger of cryptocurrency transactions that is hard for hackers to tamper with. In addition, transactions require a two-factor authentication process. For instance, you might be asked to enter a username and password to start a transaction. Then, you might have to enter an authentication code that is sent via text to your personal cell phone. While securities are in place, that does not mean cryptocurrencies are un-hackable. In fact, several high-dollar hacks have cost cryptocurrency startups heavily. Hackers hit Coincheck to the tune of $534 million and BitGrail for $195 million in 2018. That made them two of the biggest cryptocurrency hacks of 2018,