Importantly, cryptocurrencies can be exchanged for fiat currencies in special online markets, meaning each has a variable exchange rate with major world currencies, such as the U.S. dollar, British pound, European euro, and Japanese yen.
Regulation across borders has to keep up with the rapidly advancing pace of cryptocurrency development. Due to the decentralized nature of cryptocurrencies, this is a complex matter, with international disagreement ranging from the legitimacy of currency status, or even whether they should be made illegal.

Crypto gains may be fueling the labor shortage as people buck low-paying work and take their chances on risky digital assets, research firm says
Altcoins also sometimes differ in the method of verification used to authenticate transactions. While some altcoins use Proof-of-Work systems, others use Proof-of-Stake consensus, which replaces miners with validators. Proof-Of-Stake mining requires a lot less energy and fewer resources than Proof-Of-Work systems since Proof-Of-Work miners have to do much more ‘work’ to mine blocks.