Stablecoins are often proposed as one of the most logical use cases for cryptocurrencies. Unlike most cryptocurrencies, which have volatile values, stablecoins are pegged to something (usually an actual currency) to keep its value from fluctuating — making it less like a stock and more like an actual currency you can use. Now, PayPal is getting into the business of cryptocurrencies with its new stablecoin, the PayPal USD.