Tether is a unique (and controversial) cryptocurrency. It is unique in that it’s tied to existing fiat currencies. Currently, Tether supports US Dollars (USD), Euros (EUR), and in the future Japanese Yen (JPY). What this intends to accomplish is limit the volatility of the Tether cryptocurrency to that of the underlying fiat asset. All good so far.
The controversy is delineated in this TechCrunch article, not the least of which is the lack of transparency with their claims of fiat-backed cryptocurrency, which is in contradistinction to what its website states. The same article points out that:
The most interesting thing about Tether is that you don’t need to redeem them for dollars. As long as a cryptocurrency exchange believes that one Tether is worth one dollar, you can just use your Tether to buy bitcoin, or ether, or whatevercoin, and then transfer / convert that to dollars.
So, although it’s yet to be verified that Tether is a fraud, it’s very much being used. Certainly the utility of some type of fiat-based stablecoin is of interest to the crypto community in that it’s been one of the top ten cryptos for a while, in spite of its reputation.