Stablecoins are cryptocurrencies designed to minimize the volatility of the price of the stablecoin, relative to some "stable" asset or basket of assets. A stablecoin can be pegged to a currency, or to exchange traded commodities (such as precious metals or industrial metals). Stablecoins redeemable in commodities are said to be backed, whereas those leveraging fiat money or other cryptocurrencies are referred to as unbacked.
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I have never had a stable coin because the price can't go up or down. Stable coin prices such as Tether (USDT) always follow the price of the US dollar. What actual benefits do you get from stable coins and why do you keep these coins?
Stablecoins, have very specific scope. To get out of the cryptocurrency market, without leaving. Let's say I want to get my profits of Bitcoin, instead of selling and get fiat currency, I buy a stablecoin, so whatever happens, I keep my value. When it's time to reinvest, I can do easily, though a cryptocurrency exchange.