How does ETF work? and how much it important to the crypto world?

ETF is still talk of the town however the sec still delaying its approval for several circumtances.
Do you think that ETF Could Be Approved In 2019?

Please read this KuCoin blog about ETF to have a better insight into it: https://blog.kucoin.com/what-would-happen-crypto-etf-proposals-approved-sk-st