Cryptocurrencies have many potential use cases—some already real, and some still a bit theoretical. Some people also buy cryptocurrencies to hold or sell later, in the hope that their value will increase over time. Others may buy crypto because they believe in the future of decentralized finance, or want to support a specific crypto project they believe in. Before trading crypto, you should know that many cryptocurrencies are subject to extreme fluctuations in value and carry the risk of total loss of value.