What is 'Tether'?
Tether is a stable cryptocurrency claiming that each token is backed by 1 US Dollar. Tether is popular during long-term downward periods as it has it hold its value very good in the past. When prices are dwindling, people are speculating on further drops. If so, they exchange their cryptocurrencies into Tether and buy their stakes back at a later stage for a hopefully cheaper price. However this approach entails some risks. Generally speaking, Tether is great if you anticipate the market correctly. If not, you probably have to FOMO back in at higher prices.
Anyway, there are still legitimate concerns about the integrity of the project. To this date, Tether has never released an official financial audit, proving that all tokens are backed by fiat currency.