The Stablecoins are cryptocoins that designed to minimise the volatility.

There are different types of Stablecoins such as :

Backed Stablecoins:

These coins are stabilized by assets outside of cryptocoins world.

Comodity backed Stablecoins

These are backed by commodities such as precious metals like gold or silver.

Look at Digit Gold Tokens (DGT)

Fiat backed Stablecoins

thd Value of cryptocoins is based on the value of backing currency.

Look at TrueUSD (TUSD),USDTether (USDT), Libra

Cruptocurrency backed

Cryptocurrency backed  are isued with cryptocurrency

Look at DAI, Havven

Seigniorage Backed

They utilize algorithms to control money supply

Look at Basis

conclusion

The Stablecoins are more solid than bitcoin and Altcoins. So you loose less and win less from other cryptocoins. You choose

PS I have only some little money at DAI because at coinbase is the only Stablecoin you can buy.