If you decide to invest in cryptocurrencies, Bitcoin is obviously still the dominant one. However, in 2017 its share in the crypto-market has quite dramatically fallen from 90 percent to just 40 percent. There are many options currently available, with some coins being privacy-focused, others being less open and decentralized than Bitcoin and some just outright copying it.
As described in their whitepaper, Augur has set out to create the first decentralized, open-source platform for prediction markets. Based on the ideas of game theory and wisdom of the crowd, prediction markets achieve greater forecasting accuracy than any individual experts can. However, the problem with previously existing prediction markets is that they were all centralized.
Tether and other stable coins: Tether is meant to reflect the price of the US dollar. There are some criticisms to consider. But if you want a stable coin for temporary use, Tether tends to be a good choice. It isn’t an investment; it is a place to park your value in crypto when you are in-between coins. With that in mind, one should dismiss TUSD, PAX, USDC, or DAI.
The term altcoin has various similar definitions. Stephanie Yang of The Wall Street Journal defined altcoins as "alternative digital currencies," while Paul Vigna, also of The Wall Street Journal, described altcoins as alternative versions of bitcoin. Aaron Hankins of the MarketWatch refers to any cryptocurrencies other than bitcoin as altcoins.