US Dollar Tether - "Counterfeit US$" :) If I'm not mistaken, it's a service started/backed by Bitfinex. Not fully sure though.
But anyway it's a convenient option for crypto market traders during times of market turmoil. Especially those without a US$ bank account. Exchanges like Bittrex etc. offer USDT which can be bought or sold with Bitcoin and several other coins. Ethereum, Dash etc.
So it's a pegged currency like $BD and bitUSD on BitShares. The question is how closely it follows the 'real' dollar ;)
At the moment, not far off. In fact it has been fairly comforting to me over the past several days, to not be bothered too much by BTC's price. The USDT 's value remains more or less the same.
However, I do have other cryptos too besides STEEM in my portfolio. So if the general trend is downwards, the overall portfolio value declines too although having USDT does help to mitigate.
Nice, I think it is time to buy BTC however now that it is so low. Or do you have doubts any crypto might overtake it? Would be interesting to see what @Clif High says, he's not active on Steem, crazy stuff he says on YouTube, he has some webcrawler bots and I think uses Machine Learning to do sentiment analysis.
Regarding HODL there's this trader on #Dvideo making a lot of money buying low selling high so..