XSpring Digital
Tether (USDT) is the stablecoin, each Tether unit issued into circulation is backed in a one to one ratio (i.e. one Tether is one US dollar) by the corresponding fiat currency unit held in deposit by Hong Kong based Tether Limited. Tether is the most popular stable coin that has been used widely in blockchain ecosystem.
Essential details:
Whitepaper: https://tether.to/wp-content/uploads/2016/06/TetherWhitePaper.pdf
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